JP2010234837A - Air conditioner for vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a device which can secure a sufficient idle stop time by performing cooling storage during fuel cut at reduced speed while performing economy control. <P>SOLUTION: The device includes: a means (51) for setting a target temperature of an evaporator (11) for each of at least two traveling states; a means (51) for controlling a compressor capacity so as to make an actual evaporator temperature correspond to the set target temperature for each of the traveling states; cooling storage devices (12, 13) which are cooled by the evaporator (11) and seal at least two cooling storage media with different freezing points internally independently; and a means (5) for automatically stopping the engine (4) to restart the engine (4) afterwards, and restarting the engine (4) when the actual evaporator temperature reaches an engine automatic stop canceling temperature determined by an air-conditioning request. In the device, a freezing point of each of at least the two cooling storage media is set to be frozen at each of at least the two traveling states. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a vehicle air conditioner, in particular, a vehicle (hybrid vehicle) that performs idle stop (automatic engine stop) when the vehicle is stopped such as waiting for a signal (when engine power is not required), and then restarts the engine when the idle stop release condition is satisfied. And the like.

  When the evaporator temperature rises during idle stop and reaches the idle stop release temperature determined from the air conditioning request, the idle stop is released and the engine is restarted. Therefore, as a technique for ensuring a longer idle stop time, a regenerator is arranged on the downstream side of the evaporator, and the regenerator that is sealed in the regenerator is solidified by the cold air that has passed through the evaporator. In addition, there is a technique for suppressing an increase in the evaporator temperature by using the cold power stored in the cold storage agent (the amount of cold storage heat due to the latent heat of dissolution) (see Patent Document 1).

JP 2003-80933 A

  By the way, when the vehicle air conditioner having a regenerator is mounted on an idle stop vehicle, it is required to satisfy both of the following three requirements.

  Requirement 1: Cold storage is performed by a regenerator during deceleration fuel cut. This is because it is possible to drive the compressor using deceleration energy during deceleration fuel cut, and there is no fuel consumption for cold storage and no deterioration in fuel consumption.

  Requirement 2: When the compressor capacity is controlled, economy control, that is, the evaporator temperature that is the minimum required for air conditioning to save fuel, and control with reduced compressor work are performed. This is because even if the vehicle air conditioner is operated, the workload of the engine that drives the compressor can be reduced by reducing the amount of work of the compressor, and the fuel consumption can be reduced.

  Requirement 3: A sufficient idle stop time is ensured. If the evaporator temperature rises to the idle stop release temperature determined from the air conditioning request at every idle stop, the idle stop is released, and the engine is restarted, the fuel efficiency improvement effect may be insufficient. Therefore, it is necessary to solidify the cold storage agent in advance and immediately store the cold before the start of idle stop.

  However, in the technique described in Patent Document 1, only one regenerator is enclosed in the regenerator. Specifically, although two or more cool storage agents having different freezing points are enclosed, two or more cool storage agents are mixed and set as a freezing point at one point near 8 ° C. Thus, if the freezing point of the cool storage agent is one point, the above three requirements cannot be satisfied at the same time, no matter what value is set for the target temperature or freezing point of the evaporator. For example, if the evaporator target temperature is set to 3 ° C during deceleration fuel cut and 12 ° C during economy control, and the regenerator has a freezing point with a freezing point of 8 ° C, Since a temperature difference can be ensured between the freezing point of the agent (8 ° C.) and the target temperature (3 ° C.) of the evaporator during the deceleration fuel cut, the cold storage agent can be sufficiently solidified during the deceleration fuel cut. However, when the deceleration fuel cut time is short, the cold storage agent is insufficiently solidified, and sufficient idle stop time cannot be secured (that is, the above requirement 3 cannot be satisfied).

  In order to solve this problem, considering that it is necessary to store the cool storage agent in the above-mentioned economy control during operation other than during deceleration fuel cut to obtain a sufficient amount of cold storage, the evaporator The target temperature is lowered from the above 12 ° C. to, for example, 7 ° C. or less at which the regenerator can solidify. As a result, the cold storage agent can be solidified even during economy control. However, if the evaporator target temperature is lowered from 12 ° C. to 7 ° C. or less, the compressor work increases accordingly, so fuel-saving operation is not achieved. Economy control cannot be performed (that is, the above requirement 2 cannot be satisfied).

  On the other hand, even if the evaporator target temperature is set to 12 ° C during the above economy control, if the freezing point of the cool storage agent is changed from 8 ° C to 13 ° C, the cool storage agent is solidified while performing fuel-saving operation during the economy control. And a sufficient amount of cold storage can be obtained. However, in this case, since the cold storage agent is completely solidified before the deceleration fuel cut, there is no room for cold storage during the deceleration fuel cut. That is, only the cold storage using the fuel is performed during the economy control, and the cold storage agent cannot be solidified at the time of the deceleration fuel cut which is most effective for the fuel consumption (that is, the above requirement 1 cannot be satisfied).

  Therefore, an object of the present invention is to provide an apparatus that can satisfy the above three requirements, that is, can perform cold storage while performing deceleration control while performing economy control, and can secure a sufficient idle stop time.

  The present invention solves the above problems by the following means. In addition, in order to make an understanding easy, although the code | symbol corresponding to embodiment of this invention is attached | subjected, it is not limited to this.

  The present invention includes a compressor (1) driven by an engine (4) for sucking, compressing and discharging refrigerant, a condenser (7) for condensing high-temperature and high-pressure refrigerant discharged from the compressor (1), and the condenser (7 And an evaporator (11) for evaporating the refrigerant by exchanging heat between the refrigerant having a low pressure by the expansion valve (10) and the surrounding air. A refrigeration cycle; target temperature setting means for setting a target temperature of the evaporator (11) for each of at least two traveling states; and the compressor so that an actual evaporator temperature matches a target temperature set for each traveling state. Compressed by the compressor capacity control means for controlling the capacity, and the refrigerant flowing through the evaporator (11) or the cold air that has passed through the evaporator (11). A regenerator (12, 13) in which at least two regenerators with different freezing points are enclosed independently, and the engine (4) is automatically stopped when the engine automatic stop permission condition is satisfied, After that, when the engine automatic stop cancellation condition is satisfied, the engine (4) is restarted, and even if this engine automatic stop cancellation condition is not satisfied, the actual evaporator temperature reaches the engine automatic stop cancellation temperature determined from the air conditioning request. And an automatic engine stop / restart means for restarting the engine (4), and the freezing point of each of the at least two cold storage agents is set so as to solidify for each of the at least two running states.

  According to the present invention, a compressor driven by an engine for sucking, compressing and discharging refrigerant, a condenser for condensing a high-temperature and high-pressure refrigerant discharged from the compressor, an expansion valve for decompressing the refrigerant condensed by the condenser, and the expansion A refrigeration cycle including an evaporator that evaporates the refrigerant by performing heat exchange between the refrigerant whose pressure is reduced by the valve and the surrounding air, and a target temperature that sets the target temperature of the evaporator for each of at least two traveling states Setting means, compressor capacity control means for controlling the compressor capacity so that the actual evaporator temperature coincides with the target temperature set for each traveling state, and a regenerator that is cooled by the refrigerant flowing through the evaporator or the cold air that has passed through the evaporator Cold storage with at least two cold storage agents with different freezing points When the engine automatic stop permission condition is satisfied, the engine is automatically stopped, and when the engine automatic stop release condition is subsequently satisfied, the engine is restarted, and even if the engine automatic stop release condition is not satisfied An engine automatic stop / restart means for restarting the engine when the actual evaporator temperature reaches the engine automatic stop release temperature determined from the air conditioning request, and at least two of each Since the freezing point of the regenerator is set, at least two regenerators in at least two running states can be obtained by combining the evaporator target temperature set for each of the at least two running states and the freezing point of each of the at least two regenerators. Can be solidified. For example, when there are two running states and cold storage agents, if the deceleration fuel cut is set to 1 running state and the economy control time is set to another running state, the first cold storage agent has a freezing point that solidifies when the deceleration fuel cut is performed. The second cold storage agent is set at a freezing point that solidifies during economy control. Considering the case where the vehicle stops after the deceleration fuel cut from the economy control, the second cool storage agent solidifies during the economy control, and the first cool storage agent solidifies during the deceleration fuel cut. As a result, even if the deceleration fuel cut time is short and sufficient cold storage cannot be expected for the first cool storage agent, the cooling power of the second cool storage agent that has been stored in advance can be used, and the idle stop is always sufficient. Time can be secured.

It is a schematic block diagram of the vehicle air conditioner of 1st Embodiment of this invention. It is a timing chart which shows the change of the amount of cold storage of two accelerators, the state of an accelerator opening at the time of decelerating from a vehicle running state, and stopping a vehicle, an evaporator temperature, the state of a compressor. It is a flowchart for demonstrating the setting of target temperature. It is a flowchart for demonstrating the setting of an idle stop flag. It is the schematic block diagram which looked at the evaporator which has a cool storage agent of 2nd Embodiment from the vehicle front.

  FIG. 1 is a schematic configuration of a vehicle air conditioner according to a first embodiment of the present invention. In FIG. 1, the refrigeration cycle R of the vehicle air conditioner includes a compressor 1, a condenser 7, an expansion valve 10, and an evaporator 11. A compressor 1 that sucks, compresses, and discharges refrigerant is provided with an electromagnetic clutch 2 for intermittent power. Since the power of the engine 4 is transmitted to the compressor 1 via the electromagnetic clutch 2 and the belt 3, the energization and de-energization of the electromagnetic clutch 2 are intermittently performed by the engine control module 5 and the under switching module 6. Driving is intermittent.

  The high-temperature and high-pressure gaseous refrigerant discharged from the compressor 1 flows into the condenser 7 and is cooled and condensed by exchanging heat with the outside air blown from the cooling fan 8. The refrigerant condensed in the condenser 7 is decompressed to a low pressure by the expansion valve 10 and becomes a low-pressure gas-liquid two-phase state. The low-pressure refrigerant from the expansion valve 10 flows into the evaporator 11. The evaporator 11 is installed in the air conditioning case 21 of the vehicle air conditioner, and the low-pressure refrigerant flowing into the evaporator 11 absorbs heat from the air in the air conditioning case 21 and evaporates. The outlet of the evaporator 11 is connected to the suction side of the compressor 1. In this way, the refrigeration cycle R forms a closed circuit.

  In the air conditioning case 21, a blower 22 is disposed on the upstream side of the evaporator 11, and the blower 22 is provided with a blower fan 23 and a drive motor 24. On the suction side of the blower fan 23, the outside air introduction port 27 and the inside air introduction port 28 are opened and closed by the inside / outside air switching door 25. Thereby, outside air (air outside the vehicle compartment) or inside air (air inside the vehicle compartment) is switched and introduced. The inside / outside air switching door 25 is driven by an electric drive device 26 comprising a servo motor.

  On the other hand, on the downstream side of the evaporator 11, regenerators 12 and 13 and an air mix door 31, which will be described later, are sequentially arranged. A hot water heater core (heating heat exchanger) 33 that heats air using hot water (cooling water) of the engine 4 as a heat source is installed on the downstream side of the air mix door 31. A bypass passage 34 for bypassing the hot water heater core 33 and flowing air (cold air) is formed on the side (upper part) of the hot water heater core 33.

  The air mix door 31 is a rotatable plate-like door, and is driven by an electric drive device 32 composed of a servo motor. The air mix door 31 adjusts the air volume ratio between the hot air passing through the hot water heater core 33 and the cold air passing through the bypass passage 34, and the temperature of the air blown into the vehicle interior by adjusting the air volume ratio of the cold / hot air. Adjust.

  An air mixing unit 35 is provided on the downstream side of the hot water heater core 33, where the hot air from the hot water heater core 33 and the cold air from the bypass passage 34 are mixed to produce air of a desired temperature.

  Further, a defroster opening 36, a face opening 37, and a foot opening 38 are formed on the downstream side of the air mixing unit 35, and each opening has a plate-like defroster door 39, a face door 40, and a rotatable door. Opened and closed by the foot door 41. The three doors 39, 40, 41 are connected to a common link mechanism, and are driven by an electric drive device 42 including a servo motor via the link mechanism. For example, when the defroster door 39 is open, the air is directed to the inner surface of the vehicle windshield via a defroster duct (not shown), and when the face opening 37 is open, the air is directed toward the upper body of the passenger in the vehicle cabin via the face duct (not shown). However, when the foot opening 38 is open, air blows out toward the feet of the passengers in the passenger compartment through a foot duct (not shown).

  In the control amplifier 51 to which the evaporator temperature (evaporator blowing temperature) from the temperature sensor 52 and the air conditioner signal from the air conditioner switch 53 are input, the target temperature of the evaporator 11 is set for each traveling state when the air conditioner switch 53 is in the ON state. A duty signal for controlling the compressor capacity is output to the compressor 1 so that the actual evaporator temperature detected by the temperature sensor 52 matches the target temperature for each running state. For example, at the time of deceleration fuel cut that is one traveling state, a target temperature for early storage of the first cold storage agent described later is set as the first target temperature (for example, 3 ° C.). Further, in the case of a traveling state other than when the deceleration fuel is cut, a target temperature for the purpose of ensuring the minimum cooling power required for cooling is set as the second target temperature (for example, 12 ° C.). The control of the compressor 1 performed so as to obtain the second target temperature is hereinafter referred to as “economy control”.

  When the air conditioner switch 53 is turned ON, the control amplifier 51 transmits a signal for operating the compressor 1 to the engine control module 5 by the CAN communication 56. Further, the control amplifier 51 outputs an engine restart request signal when the actual evaporator temperature detected by the temperature sensor 52 reaches the engine automatic stop release temperature determined from the air conditioning request in the engine automatic stop state described later. Transmit to the control module 5. The control amplifier 51 controls the blower fan driving motor 24 so as to obtain the target air volume, and drives the electric driving devices 26, 32, and 42 for automatic control of the air outlet and the air inlet.

  The engine control module 5 controls the fuel injection amount, fuel injection timing, and ignition timing to the engine 4 based on signals from various sensors that detect the operating state of the engine 4. Further, in the eco-run vehicle and the hybrid vehicle targeted by the present invention, the engine control module 5 has an idle stop permission condition (engine automatic stop permission condition) based on the rotation speed signal, vehicle speed signal, brake signal, etc. of the engine 4. It is determined whether or not the condition is satisfied, and when the idle stop permission condition is satisfied, the engine 4 is automatically stopped by powering off the ignition device, stopping fuel injection, or the like.

  Further, the engine control module 5 determines whether or not an engine automatic stop cancellation condition is satisfied based on an accelerator signal or the like after the engine is automatically stopped. For example, when the brake pedal is released and the accelerator pedal is depressed, it is determined that the idle stop cancellation condition (engine automatic stop cancellation condition) is satisfied, and the engine 4 is automatically restarted in preparation for the start of the vehicle.

  Further, the engine control module 5 automatically restarts the engine 4 when an engine restart request signal is received from the control amplifier 51 even if the engine automatic stop cancellation condition is not satisfied.

  Further, the refrigerant pressure from the refrigerant pressure sensor 54 and the accelerator opening from the accelerator sensor 55 are input to the engine control module 5, and when the engine control module 5 determines that the compressor 1 can be operated by these signals, the compressor An ON signal is transmitted to the under switching module 6 by CAN communication 56. In the under switching module 6 that has received the compressor ON signal from the engine control module 5, the air conditioner relay in the module 6 is turned ON, and the electromagnetic clutch 2 is connected to operate the compressor 1.

  Next, a specific configuration of the regenerators 12 and 13 disposed downstream of the evaporator 11 will be described. The first regenerator 12 and the first regenerator 12 located immediately downstream of the evaporator 11 are further downstream. As shown in FIG. 1, the second regenerator 13 that is positioned has the same front area as the evaporator 11, and the entire amount of cold air that has passed through the evaporator 11 (the total amount of air in the air conditioning case 21) passes therethrough. It has a configuration. Thereby, each regenerator 12 and 13 can be made into the thin structure with a small thickness dimension with respect to the air flow direction in the air-conditioning case 21. FIG.

  The specific configuration of each of the regenerators 12 and 13 as a heat exchanger is such that a tubular member is formed of a metal such as aluminum having excellent heat conductivity, and a regenerator is accommodated inside the tubular member. It comes to be sealed. A large number of the tubular members are arranged at a predetermined interval, and the air passes through the gaps between the numerous tubular members.

  Here, the freezing point is made different between the first regenerator stored in the first regenerator 12 and the second regenerator stored in the second regenerator 13. In order to store the cold during the deceleration fuel cut, the first cold storage agent is set to a temperature slightly higher than the first target temperature (3 ° C.) that is the target temperature of the evaporator at the time of the deceleration fuel cut, for example, 5 ° C. On the other hand, since the 2nd cool storage agent accommodated in the 2nd cool storage 13 performs cool storage during economy control, it is slightly higher than the 2nd target temperature (12 degreeC) which is the target temperature of the evaporator at the time of economy control as a freezing point. Set to temperature, eg 14 ° C.

  The setting of the freezing point of each of the first and second cool storage agents is not limited to this, and the freezing point of the first cool storage agent is set to a temperature higher than the first target temperature and lower than the second target temperature. In addition, the freezing point of the second regenerator may be set to a temperature that is higher than the second target temperature and lower than the idle stop release temperature (engine automatic stop release temperature) determined from the air conditioning request. Note that a temperature higher than the second target temperature is set in advance as the idle stop release temperature.

  Next, the operation of the first embodiment will be described with reference to FIG. 2. FIG. 2 shows that when the vehicle is stopped by decelerating from the vehicle running state, the accelerator opening, the vehicle speed, the evaporator temperature, the compressor 1 The state shows how the cold storage amount of the entire first and second cold storage agents changes. However, it is assumed that economy control is performed on the compressor 1 in the vehicle running state.

  When the air conditioner switch 53 is ON, if the economy control is being performed, the compressor capacity, specifically, the refrigerant discharge capacity of the compressor 1 is set so that the evaporator temperature becomes the second target temperature (12 ° C.). Controlled by. Here, since the freezing point (14 ° C.) of the second cool storage agent is set to a temperature slightly higher than the second target temperature (12 ° C.), the evaporator temperature detected by the temperature sensor 52 is the first at the timing of t1. When the freezing point (14 ° C.) of the second cold storage agent is reached, the second cold storage agent starts to solidify, the cold storage to the second cold storage agent proceeds, and all the second cold storage agent is solidified at the timing of t2 (FIG. (See A in the middle).

  On the other hand, when the accelerator pedal is released at the timing t3 and the engine speed at that time exceeds the fuel cut speed, the deceleration fuel cut condition is satisfied and the deceleration fuel cut is started. The target temperature of the evaporator 11 is switched stepwise from the second target temperature (12 ° C.) to the first target temperature (3 ° C.). During the deceleration fuel cut, the refrigerant discharge capacity of the compressor 1 is controlled by the control amplifier 51 so that the evaporator temperature detected by the temperature sensor 52 becomes the first target temperature (3 ° C.). Here, since the freezing point (5 ° C.) of the first cold storage agent is set to a temperature slightly higher than the first target temperature (3 ° C.), the evaporator temperature is set to the freezing point ( When the temperature reaches 5 ° C., the first cool storage agent starts to solidify, the cool storage to the first cool storage agent proceeds, and all the first cool storage agent solidifies at the timing of t5 (see B in the figure).

  If the second cool storage agent has not solidified at the start timing of the deceleration fuel cut, and there is room for the second cool storage agent to store cold, the second cool storage agent is stored cold during the deceleration fuel cut. Is possible. In addition, if the idle fuel stop is started before the deceleration fuel cut time is short and all of the first cool storage agent is solidified, the cool storage of the first cool storage agent may end up being insufficient. However, since cold storage is performed on the second cold storage agent during economy control, it is possible to secure sufficient cooling power to ensure a sufficient idle stop time.

  When an idle stop permission condition (engine automatic stop permission condition) is satisfied, for example, when the brake pedal is depressed at the timing t6 and the vehicle speed is close to the stopped vehicle speed, the engine 4 is stopped by the engine control module 5. The operation of the compressor 1 is stopped by the stop.

  After the timing t6 when the operation of the compressor 1 stops, in the present embodiment, the air conditioning in the vehicle interior is maintained by the first and second cool storage agents. That is, when the evaporator temperature detected by the temperature sensor 52 rises and reaches the melting point (5 ° C.) of the first cool storage agent at the timing t7, the cold storage stored in the first cool storage agent is first performed in order to maintain the air conditioning in the passenger compartment. By using force (cold heat storage amount due to latent heat of dissolution), the evaporator temperature can be maintained at the melting point (5 ° C.) of the first cool storage agent until the timing of t8, and the rise in the evaporator temperature can be suppressed (FIG. (See C in the middle).

  The evaporator temperature rises from the timing t8 when the cooling power of the first cool storage agent is used up (that is, all the first cool storage agent is dissolved). Then, when the evaporator temperature detected by the temperature sensor 52 rises and reaches the melting point (14 ° C.) of the second cool storage agent at the timing t9, the cold stored in the second cool storage agent is now maintained for maintaining the air conditioning in the passenger compartment. By using force (cold heat storage amount due to latent heat of dissolution), the evaporator temperature can be maintained at the melting point (14 ° C.) of the second cold storage agent until the timing of t10, and an increase in the evaporator temperature can be suppressed (FIG. (See D in the middle).

  The evaporator temperature rises again from the timing t10 when the cooling power of the second cool storage agent is used up (that is, all the second cool storage agent is dissolved). When the evaporator temperature detected by the temperature sensor 52 reaches the air conditioning request idle stop release temperature at the timing t11, an engine start request is issued from the control amplifier 51 to the engine control module 5 to prevent the cooling feeling from deteriorating. . In response, the engine control module 5 releases the idle stop and restarts the engine 4. When the engine 4 is restarted, the compressor 1 can be operated, and the control amplifier 51 performs economy control on the compressor 1. That is, the target temperature of the evaporator in the economy control after the timing of t11 is the second target temperature (12 ° C.), and the refrigerant discharge capacity of the compressor 11 is controlled so that the evaporator temperature coincides with the second target temperature. Therefore, the evaporator temperature falls again from the air conditioning request idle stop release temperature.

  As described above, according to the present embodiment, in a vehicle that performs an idle stop when stopping such as waiting for a signal (when engine power is not required), even if the compressor 1 of the refrigeration cycle R stops when the vehicle stops, the first Air conditioning in the passenger compartment can be maintained by using two cooling powers of the first regenerator encapsulated in the regenerator 12 and the second regenerator encapsulated in the second regenerator 13. . As a result, the timing at which the idle stop is released can be delayed until the timing of t11, and the idle stop can be continued for a long time.

  This control executed by the control amplifier 51 and the engine control module 5 will be described with reference to the flowcharts of FIGS.

  FIG. 3 is for setting the target temperature of the evaporator 11, and is executed by the control amplifier 51 at regular intervals (for example, every 10 ms). However, it is assumed that the air conditioner switch 53 is turned on.

  In step 1, it is checked whether or not the deceleration fuel is cut. It is determined in the engine control module 5 whether or not it is during deceleration fuel cut. For example, when the engine speed when the accelerator pedal is released while the vehicle is running is equal to or higher than the fuel cut speed, the deceleration fuel cut permission condition is satisfied, so the deceleration fuel cut flag is set to 1, and the engine control module 5 The fuel cut is performed.

  The control amplifier 51 looks at this deceleration fuel cut flag transmitted from the engine control module 5. When the deceleration fuel cut flag = 1, it is determined that the deceleration fuel is being cut, and the routine proceeds to step 2 where the first target temperature is set to the target temperature of the evaporator 11. The first target temperature is determined in advance by adaptation (for example, 3 ° C.).

  When the deceleration fuel cut flag = 0 in step 1, the economy control condition is satisfied. At this time, the routine proceeds to step 3 where the second target temperature is set to the target temperature of the evaporator 11. The second target temperature is also determined in advance (for example, 12 ° C.).

  In a control routine (not shown) in the control amplifier 51, the duty given to the compressor 1 so that the actual evaporator temperature detected by the temperature sensor 52 matches the target temperature for each of the two travel states set in this way. A signal is generated and output to the compressor 1. In the compressor 1, the refrigerant discharge capacity of the compressor 1 is controlled by the duty signal so that the target temperature is set for each of the two travel states set in this way.

  FIG. 4 is for setting the idle stop flag, and is executed by the engine control module 5 at regular intervals (for example, every 10 ms).

  In step 11, an idle stop flag (initially set to zero at the start of vehicle operation) is checked. If it is now assumed that the idle stop flag = 0, the process proceeds to step 12 to check whether the idle stop permission condition is satisfied. For example, the idle stop permission condition is satisfied when the accelerator pedal is not depressed, the vehicle speed is close to zero, the brake pedal is depressed, and the like. At this time, the routine proceeds to step 14 where the idle stop flag = 1. When any one of the above conditions is not satisfied at step 12, the routine proceeds to step 13 where the idle stop flag = 0 is maintained.

  On the other hand, when the idle stop flag = 1 in step 14, since the idle stop flag = 1 in step 11 from the next time, the process proceeds to step 15 to check whether there is an engine start request from the control amplifier 51 or not. The control amplifier 51 determines whether or not the evaporator temperature detected by the temperature sensor 52 is equal to or higher than the air conditioning request idle stop release temperature. If the evaporator temperature is equal to or higher than the air conditioning request idle stop release temperature, an engine start request is issued. Is transmitted to the engine control module 5. When there is an engine start request from the control amplifier 51, step 16 is skipped and the routine proceeds to step 17, where the idle stop flag = 0 is set.

  When there is no engine start request from the control amplifier 51 at step 15, the routine proceeds to step 16 where it is determined whether or not the idle stop cancellation condition is satisfied. For example, when the brake pedal is released or the accelerator pedal is depressed with the idle stop flag = 1, the idle stop cancellation condition is satisfied. At this time, the routine proceeds to step 17 where the idle stop flag = 0. When the idle stop cancellation condition is not satisfied at step 16, the routine proceeds to step 14 where the idle stop flag = 1 is continued.

  In a control routine (not shown) in the engine control module 5, idle stop (automatic stop of the engine 4) is started at the timing when the idle stop flag is switched from zero to 1, and then the idle stop flag is switched from 1 to zero. The idle stop is released at the timing and the engine 4 is restarted.

  Thus, according to the present embodiment (the invention described in claim 1), the compressor 1 driven by the engine 4 sucks, compresses and discharges the refrigerant, and the high-temperature and high-pressure refrigerant discharged from the compressor 1 is condensed. A condenser 7 to be decompressed, an expansion valve 10 for decompressing the refrigerant condensed by the condenser 7, and an evaporator 11 for evaporating the refrigerant by performing heat exchange between the refrigerant having a low pressure by the expansion valve 10 and the surrounding air. The refrigeration cycle R, target temperature setting means (see steps 1 to 4 in FIG. 3) for setting the target temperature of the evaporator 11 for each of the two traveling states, and the actual evaporator temperature set for each traveling state. A compressor capacity control means for controlling the compressor capacity so as to coincide with a target temperature, and a regenerator that is cooled by cold air that has passed through the evaporator 11. The regenerators 12 and 13 in which two regenerators with different fixed points are independently enclosed, and the engine 4 is automatically stopped when the idle stop permission condition (engine automatic stop permission condition) is satisfied, and then the idle stop is performed. When the release condition (engine automatic stop release condition) is satisfied, the engine 4 is restarted, and even if the idle stop release condition is not satisfied, the actual evaporator temperature is the air conditioning request idle stop release temperature (the engine automatic determined by the air conditioning request). An engine automatic stop / restart means (see steps 11 to 17 in FIG. 4) for restarting the engine 4 when the stop release temperature is reached, and each of the two cold storages to solidify for each of the two running states Since the freezing point of the agent is set, the target temperature of the evaporator 11 set for each of the two traveling states and the two cold storages Of the combination of the freezing point, it is possible to solidify the two refrigerant 13A in the two running state. For example, if the deceleration fuel cut is set to 1 running state and the economy control time is set to another running state, the first cool storage agent is at the freezing point (5 ° C.) that solidifies when the deceleration fuel cut is performed, and the second cool storage agent is economy controlled. Set to freezing point (14 ° C), which sometimes solidifies. Considering the case where the vehicle stops after the deceleration fuel cut from the economy control, the second cool storage agent solidifies during the economy control, and the first cool storage agent solidifies during the deceleration fuel cut. As a result, even if the deceleration fuel cut time is short and sufficient cold storage cannot be expected for the first cool storage agent, the cooling power of the second cool storage agent that has been stored in advance can be used, and the idle stop is always sufficient. Time can be secured.

  At the time of deceleration fuel cut, the refrigerant discharge capacity of the compressor 1 is controlled so that the temperature of the evaporator 11 becomes the first target temperature (3 ° C.) lower than the freezing point (5 ° C.) of the first cold storage agent. When the evaporator temperature is lowered to the freezing point (5 ° C.) of the first cold storage agent by controlling the refrigerant discharge capacity of the compressor 1, the first cold storage agent starts to solidify and the cold storage to the first cold storage agent is started. That is, according to the present embodiment (the invention described in claim 3), the freezing point of the first cold storage agent is higher than the first target temperature (3 ° C.) that is the target temperature of the evaporator at the time of deceleration fuel cut and Since the temperature is set to a temperature (5 ° C.) lower than the second target temperature (12 ° C.), which is the target temperature of the evaporator during economy control, it is possible to store the first regenerator during the deceleration fuel cut. Since the compressor 1 is driven using the deceleration energy during the deceleration fuel cut, the first cold storage agent can be stored in a state where the fuel supply is stopped, and the fuel efficiency is improved.

  During economy control, the refrigerant discharge capacity of the compressor 1 is controlled so that the evaporator temperature becomes a second target temperature (12 ° C.) lower than the freezing point (14 ° C.) of the second cold storage agent. When the evaporator temperature is reduced to the freezing point of the second cool storage agent by controlling the refrigerant discharge capacity of the compressor 1, the second cool storage agent starts to solidify and the cold storage to the second cool storage agent is started. That is, according to the present embodiment (the invention described in claim 4), the freezing point (14 ° C.) of the second regenerator is set from the second target temperature (14 ° C.) which is the target temperature of the evaporator during economy control. And a temperature lower than the air conditioning request idle stop cancellation temperature (engine automatic stop cancellation temperature determined from the air conditioning request)), it is possible to store the second regenerator while performing economy control. Since the second cool storage agent can be stored without prohibiting economy control, it is possible to reduce fuel consumption deterioration when the vehicle air conditioner is operated while storing the cool. In addition, the cooling power stored in the second regenerator during economy control can be used as a cold power backup when the first regenerator is insufficiently refrigerating, thus ensuring sufficient idle stop time. It becomes possible to do.

  Since the cold storage to the first cold storage agent performed at the time of deceleration fuel cut is cold storage in a state where the fuel supply is stopped, there is a demand to increase the cold storage amount as much as possible in a short time. On the other hand, the greater the temperature difference between the first cool storage agent and the refrigerant that cools the first cool storage agent, the greater the amount of heat transfer and the better the cool storage efficiency of the first cool storage agent. According to the present embodiment (the invention described in claim 6), when the first and second cool storage agents are solidified by the cold air that has passed through the evaporator 11, the first cool storage agent is closest to the evaporator 11. Next, the second cool storage agent is arranged, so that the sufficiently cooled cold air is supplied to the first cool storage agent first, and the cool storage efficiency of the first cool storage agent during the deceleration fuel cut is increased. It is possible to raise. Thereby, even when the deceleration fuel cut time is short, the maximum amount of cold storage can be obtained for the first cold storage agent in a state where the fuel supply is stopped.

  FIG. 5 is a schematic configuration diagram of the evaporator 61 according to the second embodiment as viewed from the front of the vehicle. The first embodiment shown in FIG. 1 coagulates the two cold storage agents by the cold air that has passed through the evaporator 11, but the second embodiment coagulates the two cold storage agents by the refrigerant flowing through the evaporator 11. . That is, in FIG. 5, the evaporator 61 includes an upper passage 62 positioned in the left-right direction in the drawing, a lower passage 63, and a tubular member 64 communicating with the two passages 62 and 63. The tubular member 64 is made of a metal such as an aluminum tube excellent in thermal conductivity, and is arranged in a large number in the left-right direction at a predetermined interval. Therefore, the refrigerant path is composed of an upper passage, a tubular member 64, and a lower passage 63. The refrigerant flowing toward the left in the upper passage 62 is divided into a plurality of tubular members 64 and flows downward, and the lower passage 63 At this time, it flows toward the right in the lower passage 63.

  A tubular member 65 that houses the first cold storage agent 66 is disposed in the upper half of the outer periphery of the tubular member 64, and a tubular member 67 that houses the second cold storage agent 68 in the lower half of the outer periphery of the tubular member 64. Are placed close together. The first cool storage agent 66 is set to a temperature (for example, 5 ° C.) that is slightly higher than the first target temperature (3 ° C.) as a freezing point in order to perform cool storage during the deceleration fuel cut. On the other hand, the second cold storage agent is set to a temperature (for example, 14 ° C.) slightly higher than the second target temperature (12 ° C.) as a freezing point in order to perform cold storage during economy control.

  Since the cold storage to the first cold storage agent 66 performed at the time of deceleration fuel cut is cold storage in a state where the fuel supply is stopped, there is a demand to increase the cold storage amount as much as possible in a short time. On the other hand, the greater the temperature difference between the first cool storage agent 66 and the refrigerant that cools the first cool storage agent 66, the greater the amount of heat transfer and the better the cool storage efficiency of the first cool storage agent 66. According to the second embodiment (the invention described in claim 5), when the two cool storage agents 66 and 68 are solidified by the coolant flowing through the evaporator, the first cool storage agent 66 is placed upstream of the coolant path, and then Since the second cool storage agent 68 is disposed in the first cool storage agent 66, the sufficiently cooled refrigerant is supplied to the first cool storage agent 66 first, and the cool storage efficiency of the first cool storage agent 66 during the deceleration fuel cut is increased. It becomes possible. Thereby, even when the deceleration fuel cut time is short, the maximum amount of cold storage can be obtained for the first cold storage agent 66 in a state where the fuel supply is stopped.

  In the embodiment, the description has been given of the case where at least two travel states are at the time of deceleration fuel cut and economy control, and at least two cool storage agents are the first cool storage agent and the second cool storage agent. It is not something

DESCRIPTION OF SYMBOLS 1 Compressor 4 Engine 5 Engine control module 7 Capacitor 10 Expansion valve 11 Evaporator 12 1st regenerator 13 2nd regenerator 51 Control amplifier 61 Evaporator 66 1st regenerator 68 2nd regenerator

Claims (6)

A compressor driven by the engine that sucks, compresses and discharges refrigerant, a condenser that condenses the high-temperature and high-pressure refrigerant discharged from the compressor, an expansion valve that decompresses the refrigerant condensed by the condenser, and the expansion valve is at low pressure A refrigeration cycle including an evaporator that causes heat exchange between the refrigerant and ambient air to evaporate the refrigerant;
Target temperature setting means for setting a target temperature of the evaporator for each of at least two traveling states;
Compressor capacity control means for controlling the compressor capacity so that the actual evaporator temperature matches the target temperature set for each running state;
A regenerator that is cooled by the refrigerant flowing through the evaporator or the cold air that has passed through the evaporator, and in which at least two regenerators having different freezing points are independently enclosed,
The engine is automatically stopped when the automatic engine stop permission condition is satisfied, and then the engine is restarted when the automatic engine stop cancellation condition is satisfied. An engine automatic stop / restart means for restarting the engine when the evaporator temperature reaches the engine automatic stop release temperature determined by the air conditioning request,
The vehicle air conditioner is characterized in that solidification points of the at least two cold storage agents are set so as to solidify for each of the at least two running states. Each of the at least two running states is at the time of economy control that is a time when the deceleration fuel is cut and an operation other than the time when the deceleration fuel is cut,
The vehicle air conditioner according to claim 1, wherein the at least two cool storage agents are a first cool storage agent and a second cool storage agent.   The freezing point of the first regenerator is set to a temperature higher than a first target temperature that is a target temperature of the evaporator when the deceleration fuel cut is performed and lower than a second target temperature that is a target temperature of the evaporator during the economy control. The vehicle air conditioner according to claim 2, wherein the air conditioner is set.   The freezing point of the second cool storage agent is set to a temperature that is higher than a second target temperature that is a target temperature of the evaporator at the time of economy control and lower than an engine automatic stop release temperature that is determined from the air conditioning request. The vehicle air conditioner according to claim 2.   3. When the two cool storage agents are solidified by the refrigerant flowing through the evaporator, the first cool storage agent is disposed upstream of the coolant path, and the second cool storage agent is then disposed. The vehicle air conditioner described in 1.   When the two cool storage agents are solidified by cold air that has passed through the evaporator, the first cool storage agent is disposed closest to the evaporator, and the second cool storage agent is then disposed. The vehicle air conditioner according to 2.