JP2000127752A - Vehicular air conditioner having cold storage unit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent worsening of a feeling due to vibration and noises by reducing the number of starting and stop times of a sub-engine at an intermediate period where an air-conditioning load is low. SOLUTION: A vehicular air conditioner having a cold storage unit is provided with a cold storage unit 20 connected to a refrigerant system 10 through bypass of an expansion valve 14 and an evaporator 15 performs temporary execution of cold storage operation, through which a refrigerant is fed to the cold storage unit 20, and suppresses cooling capacity during cooling operation at an intermediate period during which an air-conditioning load is low and cooling operation and heating operation are alternately repeated. By executing cooling operation by the cold storage unit 20, heating capacity during heating operation is suppressed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air conditioner for a vehicle which is installed in a vehicle such as a bus and cools a vehicle compartment, and more particularly to an air conditioner for a vehicle having a cool storage unit.

[0002]

2. Description of the Related Art A vehicle air conditioner capable of providing a comfortable cabin environment to occupants and passengers by air-conditioning the cabin of a bus or the like can perform a cooling operation and a heating operation. In the cooling operation, the conditioned air cooled and dehumidified by exchanging heat with the refrigerant by passing through the evaporator is blown through a cooling duct installed in the vehicle compartment by the operation of the blower, and each air blower provided in the cooling duct is blown. It is blown out from the exit toward the passenger compartment. A refrigerant system that supplies a low-temperature and low-pressure liquid refrigerant to the evaporator compresses a low-temperature and low-pressure gas refrigerant into a high-temperature and high-pressure gas refrigerant by a compressor, and sends the gas refrigerant to a condenser to be cooled by outside air. The refrigerant condensed in the condenser is separated into gas and liquid by the receiver, and the liquid refrigerant is sent from the receiver to the expansion valve and decompressed and expanded to become a low-temperature and low-pressure liquid refrigerant, which constitutes a refrigeration cycle that is supplied to the evaporator again. I have. In the heating operation, engine cooling water is introduced into the heater core as a heating source, and air heated through the heater core is blown through a heating duct installed in the vehicle interior by the operation of the blower, and is provided in the heating duct. The air is blown out from each outlet into the passenger compartment. Some route buses adopt a system in which a plurality of radiators installed at appropriate places in a vehicle compartment are connected to directly circulate engine cooling water.

[0003] The air conditioner installed in the bus includes:
There are a sub-engine system mainly used for large sightseeing buses and a direct connection system mainly used for route buses and small buses. The sub-engine system is equipped with an engine (sub-engine) dedicated to the air conditioner separately from the driving engine (main engine) of the vehicle.
The compressor of a refrigerant system or the like is operated using the driving force of the sub-engine. In the case of the sub-engine system, main devices such as a sub-engine and a compressor are unitized, and are usually installed in a space below the passenger compartment in the center of the vehicle body. On the other hand, a direct connection type vehicle air conditioner obtains a driving force from a traveling engine of a vehicle to a refrigerant compressor or the like, similarly to a passenger car or the like. In the case of a route bus, the compressor is installed near the engine at the rear of the vehicle body,
Evaporators and condensers are often installed on the roof of a vehicle body. In the case of a small bus, the compressor is installed near the engine at the front of the vehicle, the condenser is installed below the cabin in the center of the vehicle, and the evaporator is installed above the vehicle (the ceiling) at the rear of the vehicle. Often. In the case of a bus, cooling ducts (cooling ducts) are usually installed near the left and right ceilings in the passenger compartment, and heating ducts (heating ducts).
Are located near the left and right floors in the vehicle interior.

[0004] In order to cope with recent environmental problems, it is desired to stop the idling of the engine in a parking lot or the like. Particularly, in parking lots at tourist spots and the like, idling stop regulations are sometimes enforced from the viewpoint of protecting the natural environment. For this reason, for example, the air conditioner of a sightseeing bus cannot be driven while waiting for a passenger in a summer parking lot, regardless of the sub-engine type or the direct connection type, and therefore, the temperature in the passenger compartment rises. Problem. In order to cope with such a problem, a cold storage system has been developed in which excess heat can be accumulated by utilizing excess refrigeration capacity during cooling operation. This cold storage system is configured such that cold storage panels filled with a cold storage material are arranged in parallel at a predetermined interval, and a refrigerant is introduced from a refrigerant system into a cold storage unit whose outside is surrounded by a heat insulating material such as glass wool. In addition, when the above-described air conditioner is stopped, the temperature rise in the vehicle compartment can be suppressed by releasing the cold stored in the cold storage material.

FIG. 7 schematically shows a refrigerant system having the above-described regenerative unit. In the figure, reference numeral 10 denotes a refrigerant system, 11 denotes a compressor, 12 denotes a condenser, 13 denotes a cooling / cooling storage switching solenoid valve, 14 denotes an expansion valve, 15 denotes an evaporator, 1
6 is a backflow prevention solenoid valve, and 20 is a cold storage unit. The cold storage unit 20 is provided between the condenser 12 and the expansion valve 14, and is provided in a refrigerant bypass passage 17 that joins between the evaporator 15 and the compressor 11. In the illustrated refrigerant system 10, the refrigerant circulates counterclockwise as indicated by the arrow, and is opened and closed by opening and closing the cooling / cooling storage switching electromagnetic valve 13.
Switching between a cooling operation in which the refrigerant passes through the expansion valve 14 and the evaporator 15 and a cooling operation in which the refrigerant bypasses the expansion valve 14 and the evaporator 15 and passes through the cold storage unit 20 are performed.

As a result, during normal cooling operation, the cooling / cooling switching electromagnetic valve 13 can be fully opened, and the air passing by the refrigerant supplied to the evaporator 15 can be cooled and dehumidified. In addition, when the interior of the vehicle interior drops to a desired temperature and there is a surplus in the refrigerating capacity, the cooling / cooling storage switching electromagnetic valve 13 is fully closed. Thereby, the refrigerant cools the cold storage material through the cold storage unit 20, so that cold heat is accumulated in the cold storage material. The backflow prevention solenoid valve 16 is provided for the purpose of preventing the refrigerant from flowing backward toward the cold storage unit 20 when switching from the cold storage operation to the cooling operation. Sometimes it is fully closed.

[0007]

By the way, in the case of the above-mentioned conventional sub-engine system, for example, when the air-conditioning load is low, such as in the middle period from spring to summer or from summer to autumn,
In some cases, the cooling operation and the heating operation are performed alternately because hysteresis is provided to maintain the set temperature in the vehicle compartment. In such a case, it is necessary to operate the sub engine in the cooling operation, and the refrigerant circulates through the refrigerant system by operating the compressor using the driving force of the sub engine. Then, the air sucked by the electric blower passes through the evaporator, is cooled and dehumidified, and is sent as cold air to the vehicle interior.

On the other hand, in the heating operation, the driving force of the sub-engine is not required, and the air sucked by the electric blower passes through the heater core to become hot air and is blown into the vehicle interior. That is, even in the case of the sub-engine system, the driving of the main engine cooling water is used as the hot water of the heating source supplied to the heater core, so that there is no need to operate the sub-engine.

As described above, since the cooling operation is performed intermittently in the middle period when the air conditioning load is low, the sub-engine is started and operation is started each time, and after the operation is performed for a relatively short time, Stopping is frequently repeated.
For this reason, vibration and noise frequently occur every time the sub-engine is started and stopped, and it is difficult to completely shut off the influence on the vehicle interior. Some countermeasures have been desired to provide an environment and improve the marketability.

[0010] Therefore, an object of the present invention is to reduce the number of times the sub-engine is started and stopped in the middle period when the air-conditioning load is low, and to improve the feeling deterioration due to vibration and noise.

[0011]

Means for Solving the Problems To solve the above problems, the present invention employs the following means. An air conditioner for a vehicle including the cold storage unit according to claim 1, a compressor that compresses a low-temperature and low-pressure gas refrigerant, a condenser that cools a high-temperature and high-pressure gas refrigerant supplied from the compressor with outside air, A receiver for separating the refrigerant condensed by the condenser into gas and liquid; an expansion valve for reducing and expanding the liquid refrigerant sent from the receiver; and a heat exchange between the low-temperature and low-pressure liquid refrigerant from the expansion valve and the air in the passenger compartment. A refrigerant system comprising an evaporator for cooling and dehumidifying the cooling system, comprising a regenerative storage unit connected by bypassing the expansion valve and the evaporator, and having a low air conditioning load and alternately repeating a cooling operation and a heating operation. In the period, the cold storage operation for supplying the refrigerant to the cold storage unit is temporarily performed to suppress the cooling capacity at the time of the cooling operation, and the cooling operation from the cold storage unit is performed. It is characterized in that inhibited heating capacity during tufts operation.

According to the air conditioner for a vehicle provided with such a cool storage unit, the cooling operation and the heating operation are suppressed by using the cool storage unit. Therefore, the number of times of starting and stopping the sub-engine can be reduced.

According to the vehicle air conditioner having the cool storage unit of the second aspect, when the cooling capacity is suppressed, the refrigerant is alternately supplied to the evaporator and the cool storage unit. .

According to the vehicle air conditioner provided with such a cold storage unit, the supply destination of the refrigerant is alternately switched between the evaporator and the cold storage unit, so that the refrigerant is used for storing cold heat in the cold storage unit. The time period used for cooling and dehumidifying the air by the evaporator is reduced by the time period, and as a result, the capacity of the cooling operation is suppressed.

According to a third aspect of the present invention, there is provided an air conditioner for a vehicle having a cool storage unit, wherein the heating operation and the cooling operation are performed alternately when the heating capacity is suppressed.

According to the vehicle air conditioner provided with such a cold storage unit, the heating operation and the cooling operation are alternately switched, so that the warm air generated by the heating operation and the cool air generated by the cooling operation act on the sub-engine. Since the air is supplied alternately without operation, the capacity of the heating operation is suppressed as a result.

According to a fourth aspect of the present invention, there is provided an air conditioner for a vehicle having a cool storage unit, wherein the heating operation and the cooling operation are performed simultaneously when the heating capacity is suppressed.

According to the air conditioner for a vehicle having such a cold storage unit, the warm air generated by the heating operation and the cool air generated by the cooling operation are mixed, and as a result, the heating operation performance is suppressed.

[0019]

Embodiments of the present invention will be described below with reference to the drawings. 1 to 3 show an example in which a sub-engine type vehicle air conditioner installed in a large sightseeing bus includes a cool storage unit.

FIG. 1 is a perspective view showing the outline of a sightseeing bus, in which an air conditioning unit 1 is installed below the cabin in the center of the vehicle body, and an air conditioning duct 5 connected to the air conditioning unit 1 is branched right and left. Further, the cooling / heating switching damper storage units 6 and 6 are branched into cooling ducts 7 and 7 directed toward the upper part of the vehicle compartment and heating ducts 9 and 9 directed toward the floor of the passenger compartment. This air conditioning unit 1
Is a unit in which a refrigerant system such as a compressor driven by a sub engine, a heater core, and the like are unitized. The air-conditioning unit 1 is connected to the regenerative storage unit 20 which is similarly installed adjacent to the lower part of the center of the vehicle body by the refrigerant pipes 2 and 3 and the connection duct 4.

FIG. 2 is a front view of the air conditioning unit 1 and the cold storage unit 20 as viewed from the side of the vehicle body. In the figure, reference numeral 1 denotes a sub-engine type air conditioning unit, 1a denotes a blower for blowing air driven by an electric motor, 4 is a duct for introducing air inside the vehicle
a and a connecting duct where the cold storage air introduction duct 4b joins
Reference numerals a and 8b denote cooling / cooling storage switching dampers.

FIG. 3 shows a refrigerant system 1 having a cold storage unit 20.
0 is a system diagram showing a configuration of the compressor 11 during normal cooling operation, the compressor 11 is operated with the sub engine 11a as a drive source,
Compresses low-temperature, low-pressure gas refrigerant. The high-temperature and high-pressure gas refrigerant is sent to the condenser 12 and exchanges heat with the outside air. As a result, the high-temperature and high-pressure gas refrigerant is cooled and condensed, and further sent to the receiver 18 to separate gas and liquid. The high-temperature and high-pressure liquid refrigerant passes through the dryer 19 and expands.
Led to. The high-temperature and high-pressure liquid refrigerant decompressed and expanded in the expansion valve 14 becomes a low-temperature and low-pressure liquid refrigerant, and becomes the evaporator 1.
5 to the evaporator 1
Cooling and dehumidifying by heat exchange with the air passing through 5. The refrigerant that has become a low-temperature and low-pressure gas refrigerant due to this heat exchange returns to the compressor 11 and is compressed again. Thereafter, such a clockwise circulation is repeated to form a refrigeration cycle.

During normal cooling operation, the air in the passenger compartment is sucked by the operation of the blower 1a, and is guided to the air conditioning unit 1 through the introduction duct 4a and the connection duct 4. At this time, both the cooling / cooling changeover dampers 8a and 8b have their inlets and outlets closed so that the introduced air in the passenger compartment does not pass through the cool storage unit 20. The introduced air that has been air-conditioned by passing through the evaporator in the air-conditioning unit 1 is guided to the cooling / heating switching damper storage unit 6 by the air-conditioning duct 5, and the cooling / heating switching damper here closes the heating duct side. And flows out of each outlet into the vehicle interior.

On the other hand, between the dryer 19 and the expansion valve 14, a refrigerant pipe (hereinafter, referred to as a bypass refrigerant outward path) 2 for guiding a high-temperature and high-pressure liquid refrigerant to the cool storage unit 20 is provided in a branched manner. On the expansion valve 14 side of the branch portion, there is provided a cooling / cooling storage switching electromagnetic valve 13 for switching the refrigerant flow path between a normal cooling operation and a cold storage operation described later. The cold storage unit 20 includes a plurality of cold storage panels 21 filled with a cold storage material arranged at predetermined intervals. In the illustrated case, the three cold storage panels 21 constitute one unit, and a cold storage electromagnetic valve 22 is provided at a refrigerant inlet.
Are provided, and a total of 12 cold storage panels are arranged in parallel in 4 units. An expansion valve 23 is provided at the refrigerant inlet of each cold storage panel 21 on the downstream side of the cold storage electromagnetic valve 22. The cold storage panel 21, the cold storage electromagnetic valve 22, and the expansion valve 23 are entirely made of glass wool. And the like. In addition, each cold storage panel 21
The refrigerant that has cooled the cold storage material through the
The refrigerant is returned to the upstream side of the compressor 11 through a bypass refrigerant return path 3, which prevents the refrigerant from flowing back to the cold storage unit 20 when the operation is switched from the cold storage operation to the cooling operation. A check valve 16 is provided for this purpose.

The cool storage unit 20 opens the cooling / cooling switching solenoid valve 13 from the fully opened state when a surplus occurs in the normal cooling operation, that is, when the vehicle interior is sufficiently cooled to a predetermined air-conditioning temperature. At the same time, the cold storage electromagnetic valve 22 and the backflow prevention electromagnetic valve 16 are switched from fully closed to fully open, and a high-temperature and high-pressure liquid refrigerant supplied from the receiver 18 and passed through the dryer 19 is introduced. The high-temperature and high-pressure liquid refrigerant introduced into the cold storage unit 20 through the bypass refrigerant outward path 2 is decompressed and expanded by the expansion valve 23 to become a low-temperature and low-pressure liquid refrigerant, and cools the cold storage material when passing through the cold storage panel 21. Therefore, cold heat is accumulated in the cold storage material. When the normal cooling operation is required again, for example, when the temperature in the passenger compartment becomes higher than a predetermined value, the cooling / cooling switching electromagnetic valve 13 is switched from fully closed to fully opened, and the cooling / cooling electromagnetic valve 22 and the backflow prevention are controlled. The electromagnetic valve 16 is switched from fully open to fully closed, and the refrigerant flow path is switched so that the refrigerant flows through the expansion valve 14 and the evaporator 15. Switching between the cooling operation and the cold storage operation, which is performed by opening and closing the above-described solenoid valves, is generally performed based on data input from a temperature sensor or the like disposed at an appropriate position, based on air (not shown). Processed by the control unit of the harmony device.

Next, the cooling operation of the cool storage unit 20 will be described. This cooling operation is performed by the sub engine 1
When you ca n’t drive or do n’t want to drive 1a,
In addition, it is performed when it is desired to prevent or minimize the temperature rise in the vehicle interior. When the cool heat of the cool storage unit 20 is released, the air in the passenger compartment is sucked by the operation of the blower 1a.
Both a and 8b are opened and closed so that the introduced air in the vehicle compartment passes through the cold storage unit 20. Then, the air sucked from the vehicle compartment is cooled by passing through the cold storage unit 20, guided to the cold storage air introduction duct 4 b and the connection duct 4 and enters the air conditioning unit 1. At this time, since the supply of the refrigerant to the evaporator of the air conditioning unit 1 has been stopped, the cold storage air simply passes through the evaporator, and is then guided to the cooling / heating switching damper storage unit 6 by the air conditioning duct 5 in the same manner as during normal cooling operation. Then, the air flows further into the cooling duct 7 and flows out of each outlet into the vehicle interior.

Next, a hot water circuit for supplying the main engine cooling water (hot water) as a heat source to the air conditioning unit 1 will be briefly described with reference to FIG. This hot water circuit 30
A portion included in the air conditioning unit 1 surrounded by a two-dot chain line;
The other parts, that is, parts that are attached to the vehicle in advance are connected. The front heater 49 surrounded by a dashed line is a part that is normally included on the vehicle side as an option. In FIG. 4, reference symbol E denotes a main engine that drives the vehicle, 31 denotes a radiator,
Reference numeral 32 denotes a cooling water pump, 33 denotes a thermo valve, and 34 denotes a condensate tank. The cooling water pump 32 operates to circulate the main engine cooling water, and the heat generated by the operation of the main engine E is transferred from the radiator 31 to the atmosphere. This constitutes a cooling system of the main engine E that dissipates heat. Such a main engine cooling system is connected to an air conditioner via hot water stop valves 35 and 36 provided in hot water flow paths branched from an outlet and an inlet of the main engine E, respectively.

A strainer 37 and a hot water pump 38 are provided downstream of the hot water stop valve 35 in the branch flow path on the main engine outlet side for supplying main engine cooling water from the main engine cooling system to the air conditioner side. The main engine cooling water pressurized by the hot water pump 38 is sent to a heating system 40 in the air conditioning unit 1. The heating system 40 includes a preheater 41, a hot water control valve 42, and a heater core 43 as main components, and the main engine cooling water that has heated the air through the heater core 43 passes through the hot water stop valve 36 and is again supplied to the main engine E. Returned to the cooling water system. Among them, the hot water control valve 42 has a function of adjusting the flow rate of the main engine cooling water introduced into the heater core 43, and the flow rate control by the hot water control valve 42 is performed based on the set temperature of the heating and the actual temperature of the vehicle interior. This is performed by changing the valve opening determined by a control unit (not shown) based on input information such as the above.

FIG. 5 shows the open / closed state of the hot water control valve 42 which is basically a three-way valve. FIG. 5A shows the entire amount of the main engine cooling water flowing to the heater core bypass passage 44 which bypasses the heater core 43. The state of flowing (hereinafter, referred to as a bypass position), and the state (b), in which the entire amount of the main engine cooling water is guided to the heater core 43 through the heater core main flow path 45 which is a hot water supply flow path (hereinafter, referred to as a main position). (C) shows a state in which the main engine cooling water flows while being divided into the heater core bypass flow path 44 and the heater core main flow path 45 (hereinafter, referred to as an intermediate position). As described above, the valve opening state of the hot water control valve 42 is changed by the operation of the valve elements 42a and 42b, and the flow rate of the main engine cooling water passing through the heater core 43 can be adjusted between 0 and 100%.

The main engine cooling water introduced from the cooling water system of the main engine E is guided to the above-described heater core 43 and used for a heating operation. In addition, for example, an evaporator for introducing a refrigerant during a cooling operation to cool and dehumidify air. Fifteen
(See FIG. 4). The defrost heater 46 opens the defrost solenoid valve 47 when removing frost adhering to the evaporator 15, and introduces main engine cooling water as a heat source. Further, by opening the front heater solenoid valve 48, the main engine cooling water is also supplied to the front heater 49 provided for heating around the driver's seat. Reference numeral 50 denotes a piping of the hot water circuit 30 for introducing the main engine cooling water from the main engine E installed at the rear part of the vehicle body to the heater core 43, and a heating duct disposed on the left and right floors in the passenger compartment. 9 (see FIG. 1).

The vehicle air conditioner provided with the regenerative storage unit 20 configured as described above performs the operation described below in the middle period when the air conditioning load, that is, the cooling load or the heating load is low.

For example, when the season changes from spring to summer, even if the temperature inside the vehicle compartment is high and cooling operation is required, there is no cooling load that is as large as in summer. For this reason, even if cooling operation is performed in the operation mode with the lowest cooling capacity,
The temperature drops to the set temperature in a relatively short time, and becomes lower than the set temperature by the set amount of the hysteresis. During this time, the sub-engine 11a continues to operate and supplies the refrigerant by the compressor 11, but in order to maximize the time during which the sub-engine 11a is continuously operated, it is necessary to further suppress the cooling capacity.

Therefore, during the cooling operation, the refrigerant supply destination is alternately switched to the evaporator 15 and the cold storage unit 20 for operation. That is, by alternately performing the cooling operation for supplying the refrigerant to the evaporator 15 and the cold storage operation for supplying the refrigerant to the cold storage unit 20, the cooling performance as a whole is reduced even when the sub-engine 11a is continuously operated. Can be. This operation switching operation can be performed by opening / closing the cooling / cooling switching electromagnetic valve 13 by a control unit (not shown). As a result, the refrigerant supplied by the compressor 11 when the sub-engine 11a is operated functions as the refrigerant for the cooling operation only during the period when it is supplied to the evaporator 15, and the time period when it is supplied to the cold storage unit 20 is the accumulation of cold heat. Used for In addition, the ratio of the operation time in which the cooling operation and the cold storage operation are alternately switched may be appropriately changed according to a calculated value calculated from conditions such as various sensors and a set temperature.

Even if the cooling capacity is reduced in this way, the cooling load is small, and the cooling capacity eventually drops below the set temperature, and further, after the temperature in the vehicle interior drops by the set hysteresis,
This time, the heating operation is performed. At this point, the sub engine 11a stops operating, but the blower 1a driven by the electric motor continues to blow air. Since the heating operation started in this way is not a large heating load,
It is preferable that the heating capacity is suppressed as much as possible so that it takes time until the temperature rises to the temperature at which the cooling operation is started.

Therefore, the heating operation in the operation mode having the lowest heating capacity and the cooling operation from the cool storage unit 20 are alternately performed. That is, the heating operation for supplying the main engine cooling water to the heater core 43 and the cold storage unit 2
By alternately performing the cooling operation in which the cooling heat is cooled from 0, the cooling capacity as a whole is reduced. The operation switching operation is performed by a control unit (not shown), and can be performed by opening and closing the cooling / cooling switching dampers 8a and 8b and controlling the opening of the hot water control valve 42. As a result, the air sucked into the blower 1a becomes hot air when the main engine cooling water is supplied to the heater core 43, and
When passing through the cold storage unit 20, the air becomes cold air and is supplied into the vehicle interior. Therefore, even if the compressor 11 is not operated, in other words, the sub engine 11a is not operated, the hot air and the cold air are alternately generated. Since it can be blown out, the heating capacity can be reduced as a whole.

In order to lower the heating capacity, the heating operation and the cooling operation are alternately performed as described above. In addition, the heating operation and the cooling operation in the operation mode with a low heating capacity are simultaneously performed. May be. In this case, since the cool air that has passed through the cold storage unit 20 is heated by the heater core 43, the air temperature before heating is lower than that in which the air that is not sucked by the blower 1a and passed through the cold storage unit 20 is heated. Become. In other words, if the heating capacities of the heater cores 43 are the same, the temperature of the hot air is also reduced by the lower initial temperature, and as a result, the heating capacity is reduced.

FIG. 6 is a diagram for explaining the operation of the vehicle air conditioner of the present invention, which is capable of performing an operation in which the cooling capacity and the heating capacity are reduced in the middle period when the air conditioning load is low. (A) shows the case of the conventional apparatus, and (b) shows the case of the apparatus of the present invention. In each of the figures, the vertical axis represents the cooling load, and the horizontal axis represents time. At first, the cooling load decreases with the lapse of time due to the execution of the cooling operation, in other words, the vehicle interior temperature decreases.

In the case of (a), at time ta1, the operation is switched from the cooling operation to the heating operation, and the sub-engine stops. Then, when the cabin temperature rises and the cooling load increases due to the execution of the heating operation, the cooling operation is started again at time ta2, and thereafter, similarly from the cooling operation to the heating operation at time ta3,
At time ta4, the operation is switched from the heating operation to the cooling operation, so that the operation stop and operation of the sub-engine 11a are repeated each time. Note that the greater the slope in the figure, the greater the cooling capacity and heating capacity.

On the other hand, in the case of (b), since the cooling capacity and the heating capacity are reduced, the inclination is reduced, and the time tb1 at which the cooling operation is first switched to the heating operation is longer than the time ta1 described above. . Also, a time tb2-t from when the heating operation is first switched to the cooling operation.
b1 is also longer than the conventional ta2-ta1, and it can be seen that if the operation time is the same, the number of times of switching between the cooling operation and the heating operation, that is, the number of times of starting and stopping the sub-engine 11a can be reduced. .

In FIGS. 6A and 6B, the vertical axis is the cooling load. However, when the heating operation is first performed, the vertical axis may be the heating load.

[0041]

According to the vehicle air conditioner provided with the cool storage unit of the present invention described above, the cooling capacity and the heating capacity are reduced by effectively utilizing the cool storage unit in the middle period when the air conditioning load is low. In addition, the switching cycle between the cooling operation and the heating operation can be lengthened. As a result, the number of starts and stops of the sub-engine that drives the compressor can be reduced, and the effect of improving the feel of the sub-engine due to vibration and noise at the start and stop of the sub-engine and improving the product quality can be reduced. Play.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an embodiment of a vehicle air conditioner including a cool storage unit according to the present invention, showing a case of a sub-engine system.

FIG. 2 is a front view of the air conditioning unit and the cool storage unit of FIG. 1 as viewed from the side of the vehicle body.

FIG. 3 is a diagram illustrating a configuration of a refrigerant system including the cold storage unit of FIG. 1;

4 is a diagram showing a configuration of a hot water circuit that supplies hot water to a heating system of the vehicle air conditioner including the cold storage unit of FIG. 1;

FIG. 5 is a view showing an open / close state of the hot water control valve in FIG. 4;
(A) is a bypass position, (b) is a main position, and (c) is an intermediate position.

FIGS. 6A and 6B are diagrams for explaining the operation of the present invention, wherein FIG.
(B) shows the case of the present invention, and (b) shows the case of the present invention.

FIG. 7 is a configuration diagram illustrating an outline of a refrigerant system including a cold storage unit.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Air-conditioning unit (sub-engine system) 5 Air-conditioning duct 6 Cooling / heating switching damper storage part 7 Cooling duct 9 Heating duct 10 Refrigerant system 11 Compressor 11a Sub-engine 12 Capacitor 13 Cooling / cold storage switching electromagnetic valve 14 Expansion valve 15 Evaporator 16 Backflow prevention electromagnetic Valve 18 Receiver 20 Cool storage unit 30 Hot water circuit 31 Radiator 32 Cooling water pump 33 Thermo valve 40 Heating system 42 Hot water control valve 43 Heater core E Main engine

Claims (4)

[Claims] 1. A compressor for compressing a low-temperature and low-pressure gas refrigerant, a condenser for cooling a high-temperature and high-pressure gas refrigerant supplied from the compressor with outside air, and a receiver for separating the refrigerant condensed by the condenser into gas and liquid. And an expansion valve that reduces and expands the liquid refrigerant sent from the receiver, and an evaporator that receives the low-temperature and low-pressure liquid refrigerant from the expansion valve and exchanges heat with air in the passenger compartment to cool and dehumidify the liquid refrigerant. The refrigerant system is
A cold storage unit connected by bypassing the expansion valve and the evaporator, and in a middle period in which the air conditioning load is low and the cooling operation and the heating operation are alternately repeated, a cold storage operation for supplying a refrigerant to the cold storage unit is temporarily performed. Air for a vehicle equipped with a cold storage unit, characterized in that the cooling capacity during the cooling operation is suppressed, and the cooling capacity during the heating operation is suppressed by performing the cooling operation from the cold storage unit. Harmony equipment. 2. The air conditioner according to claim 1, wherein a coolant is alternately supplied to the evaporator and the cold storage unit when the cooling capacity is suppressed. 3. The air conditioner according to claim 1, wherein a heating operation and a cooling operation are performed alternately when the heating capacity is suppressed. 4. The vehicle air conditioner equipped with a cool storage unit according to claim 1, wherein the heating operation and the cooling operation are performed simultaneously when the heating capacity is suppressed.