JP2014172422A - Air conditioner for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an air conditioner for a vehicle containing a plurality of evaporators, capable of keeping comfortableness of a passenger while preventing a time period in which an engine is automatically stopped from being excessively shortened.SOLUTION: A first evaporator for air-conditioning a front seat side includes a cool storage agent, but a second evaporator for air-conditioning a rear seat side includes no cool storage agent. An evaporator temperature threshold value which is compared with a first evaporator temperature is set to be lower in the case in which a passenger is seated on a rear seat than in the case in which no passenger is seated on the rear seat. An engine which is a power source for a compressor is started while idling stop control is performed, in short, when the first evaporator temperature comes to be an evaporator temperature threshold value or higher while the engine is automatically stopped. Thus, regardless of whether a passenger is seated on the rear seat or not, comfortableness of a passenger is maintained while the time period in which the engine is automatically stopped is not excessively shortened.

Description

  The present invention relates to a vehicle air conditioner that air-conditions a vehicle interior of a vehicle that is controlled to automatically stop an engine.

  For example, Patent Document 1 discloses a vehicle air conditioner that air-conditions a vehicle interior of a vehicle in which idling stop control, which is control for automatically stopping the engine when the vehicle is stopped, is performed. The refrigeration cycle of the vehicle air conditioner includes one evaporator for cooling the air blown into the passenger compartment and a compressor driven by the engine. And since a compressor is driven by an engine, if an engine stops, a compressor will also stop. In the vehicle of this Patent Document 1, when the temperature of the evaporator becomes a predetermined allowable value or more during idling stop control, that is, during automatic engine stop, the engine and the compressor are started. As a result, passenger comfort can be prevented from being impaired.

  Moreover, the evaporator which has a cool storage material is disclosed by patent document 2, for example. For example, the evaporator includes a cool storage material so that a part of the plurality of fins is replaced with a cool storage material in a core portion in which a plurality of refrigerant tubes and a plurality of fins are alternately stacked. Yes.

JP 2001-310620 A JP 2010-91250 A

  In the vehicle air conditioner of Patent Document 1 described above, if Patent Document 2 is taken into consideration, the temperature rise of the evaporator is suppressed by providing a cold storage material in the evaporator, thereby comforting the occupant during the automatic stop of the engine. It is conceivable to extend the stop time of the engine and the compressor while maintaining the performance.

  However, unlike the vehicle air conditioner disclosed in Patent Document 1, in the vehicle air conditioner provided with a plurality of evaporators, each of the plurality of evaporators cools the air blown to different locations in the vehicle interior. Can be considered. In such a vehicle air conditioner, for example, when a cold storage material is provided in one of a plurality of evaporators, the same control as in Patent Document 1 is performed while the engine is automatically stopped. If the value is compared with the temperature of the evaporator with the cold storage material, the temperature of the evaporator other than the evaporator with the cold storage material may exceed the allowable value. If so, passenger comfort will be impaired.

  In view of the above, the present invention is a vehicle air conditioner having a plurality of evaporators, and maintains passenger comfort while avoiding unnecessary shortening of the time during which the engine is automatically stopped. It aims at providing the vehicle air conditioner which can do.

In order to achieve the above object, according to the first aspect of the present invention, in a vehicle that is controlled to automatically stop the engine (12), the vehicle interior including the first seat and the second seat of the vehicle is air-conditioned. A vehicle air conditioner,
A first evaporator (26) that is provided with a cold storage material (30) and that cools the air blown into the vehicle interior space around the first seat with a refrigerant in the refrigeration cycle (14);
A second evaporator (28) having a lower ability to store cold than the first evaporator, and cooling the air blown into the vehicle interior space around the second seat with a refrigerant;
A compressor (18) driven by the engine to compress and circulate the refrigerant in the refrigeration cycle;
The evaporator temperature threshold (Tex) is set to a different value depending on whether or not an occupant is in the second seat, and the temperature of the first evaporator (Te1) is set to the evaporator temperature threshold during the automatic engine stop. A control device (16) for starting the engine in the case of the above is provided.

  According to the above-described invention, the engine and the compressor are started when the temperature of the first evaporator becomes equal to or higher than the evaporator temperature threshold during the automatic stop of the engine, and the evaporator temperature threshold is set in the second seat. Since the value is set differently depending on whether or not the occupant is on board, the engine is automatically stopped regardless of whether the occupant is in the second seat or not. It is possible to maintain passenger comfort while avoiding unnecessary shortening of time.

  In addition, each code | symbol in the parenthesis described in this column and the claim respond | corresponds to each code | symbol described in embodiment mentioned later.

1 is a schematic diagram illustrating an overall configuration of a vehicle air conditioner 10 according to a first embodiment. It is a flowchart which shows the control processing of the electronic controller 16 for an air conditioning of FIG. 1 in 1st Embodiment. FIG. 3 is a diagram showing a predetermined relationship between an outside air temperature Tam and an evaporator temperature threshold value Tex used for setting the evaporator temperature threshold value Tex in S140 and S150 of FIG. 2. It is a time chart for demonstrating the control processing shown to the flowchart of FIG. 2, Comprising: It is a time chart when a passenger | crew is not boarding a backseat. It is a time chart for demonstrating the control processing shown to the flowchart of FIG. 2, Comprising: It is a time chart in case a passenger | crew is boarding a backseat. It is a schematic diagram which shows the whole structure of the vehicle air conditioner 10 in 2nd Embodiment. It is a flowchart which shows the control processing of the electronic controller 16 for an air conditioning of FIG. 6 in 2nd Embodiment. It is a time chart for demonstrating the control processing shown to the flowchart of FIG. 7, Comprising: It is a time chart when a passenger | crew is not boarding a backseat. It is a flowchart which shows the control processing of the electronic controller 16 for an air conditioning of FIG. 1 in 3rd Embodiment. It is a figure which shows the relationship between the outside temperature Tam and the evaporator temperature threshold value Tex which were used in advance according to the solar radiation amount Ts used in order to set the evaporator temperature threshold value Tex in S142 and S152 of FIG. In other embodiment, it is a schematic diagram which shows the whole structure of the vehicle air conditioner 10 for demonstrating the air temperature sensor 70 provided immediately after the air flow downstream of the 1st evaporator 26. FIG.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following embodiments, the same or equivalent parts are denoted by the same reference numerals in the drawings.

(First embodiment)
FIG. 1 is a schematic diagram showing the overall configuration of a vehicle air conditioner 10 according to the first embodiment of the present invention. The vehicle air conditioner 10 according to the present embodiment is mounted on a vehicle in which control for automatically stopping the engine 12 when the vehicle is stopped such as waiting for a signal, that is, idling stop control is performed. And the vehicle air conditioner 10 air-conditions the vehicle interior of the vehicle. The vehicle is an engine vehicle that uses the engine 12 as a driving force source, but may be a hybrid vehicle that includes a traveling motor in addition to the engine 12.

  As shown in FIG. 1, the vehicle air conditioner 10 includes a refrigeration cycle 14 and an air conditioning electronic control device 16. The refrigeration cycle 14 in FIG. 1 is a vapor compression refrigeration cycle, and is a compressor or compressor 18, a condenser or condenser 20, a first expansion valve 22, a second expansion valve 24, and a first evaporator or first. One evaporator 26 and a second evaporator, that is, a second evaporator 28 are provided.

  The compressor 18 sucks, compresses and discharges the refrigerant in the refrigeration cycle 14, thereby circulating the refrigerant in the refrigeration cycle 14. The compressor 18 is connected to the engine 12 by a belt or the like, and is driven by the engine 12. Therefore, if the engine 12 stops, the compressor 18 also stops.

  The high-temperature and high-pressure superheated gaseous refrigerant discharged from the compressor 18 flows into the condenser 20. The condenser 20 cools and condenses the refrigerant by exchanging heat with outside air blown by a blower (not shown).

  Since the first expansion valve 22 and the first evaporator 26 and the second expansion valve 24 and the second evaporator 28 are provided in parallel in the refrigerant flow of the refrigeration cycle 14, they are condensed from the condenser 20 and are gas-liquid. The separated liquid refrigerant is sent out to each of the first expansion valve 22 and the second expansion valve 24.

  The first expansion valve 22 depressurizes the liquid refrigerant from the condenser 20 to a low pressure so as to be in a low pressure gas-liquid two-phase state. The refrigerant from the first expansion valve 22 flows into the first evaporator 26. The first expansion valve 22 includes a mechanical mechanism that prevents the refrigerant from flowing through the first expansion valve 22 when the compressor 18 stops. That is, the first expansion valve 22 also functions as an open / close switching valve that allows the refrigerant to flow while the compressor 18 is being driven, while preventing the refrigerant from flowing while the compressor 18 is stopped.

  The second expansion valve 24 is the same as the first expansion valve 22 described above, and the arrangement position in the refrigeration cycle 14 is different from that of the first expansion valve 22. The refrigerant from the second expansion valve 24 flows into the second evaporator 28.

  The 1st evaporator 26 is accommodated in the air-conditioning case not shown arrange | positioned, for example in the vehicle interior of the front seat vicinity. The first evaporator 26 cools the air blown into the passenger compartment by the refrigerant in the refrigeration cycle 14, that is, the refrigerant from the first expansion valve 22. In detail, the 1st evaporator 26 cools the air blown into the vehicle interior space around the front seat arrange | positioned in the vehicle interior among the air blown into the vehicle interior. In other words, the first evaporator 26 is a front seat side air conditioning evaporator. The driver's seat is included in the front seat of the vehicle.

  Moreover, the 1st evaporator 26 is provided with the core part which the air blown off to said vehicle interior space passes, and heat-exchanges the air and refrigerant | coolant. For example, the core portion includes a plurality of refrigerant tubes and a plurality of fins that are alternately stacked, and includes a regenerator material 30 that is stored cold by being cooled by a refrigerant flowing through the refrigerant tubes. Yes. For example, the cold storage material 30 is provided in the core portion of the first evaporator 26 so as to be replaced with a part of the plurality of fins respectively positioned between the refrigerant tubes. The cold storage material 30 is made of paraffin, for example.

  The first evaporator 26 includes a first evaporator temperature sensor 32 that detects a first evaporator temperature Te <b> 1 that is the temperature of the first evaporator 26. The first evaporator temperature sensor 32 is fixed to, for example, a refrigerant tube or fin constituting the first evaporator 26, and detects the surface temperature of the refrigerant tube or fin.

  For example, the second evaporator 28 is accommodated in an air conditioning case (not shown) disposed in the passenger compartment near the rear seat. Specifically, it is housed in an air conditioning case different from the air conditioning case in which the first evaporator 26 is housed. Then, the second evaporator 28 cools the air blown into the vehicle interior by the refrigerant from the second expansion valve 24. Unlike the first evaporator 26, the second evaporator 28 cools the air blown into the vehicle interior space around the rear seat disposed in the vehicle interior, out of the air blown into the vehicle interior. That is, the second evaporator 28 is a rear seat side air conditioning evaporator. The rear seat is arranged behind the front seat in the vehicle traveling direction. The front seat corresponds to the first seat in the present invention, and the rear seat corresponds to the second seat in the present invention, but the opposite relationship may be used.

  The second evaporator 28 includes a core portion in which a plurality of refrigerant tubes and a plurality of fins are alternately stacked, as in the first evaporator 26, but does not include the regenerator 30. Therefore, the temperature of the second evaporator 28 is higher than that of the first evaporator 26 when the compressor 18 is stopped. In short, the second evaporator 28 has a lower ability to store cold than the first evaporator 26.

  The refrigerant outlet 26 a of the first evaporator 26 and the refrigerant outlet 28 a of the second evaporator 28 are each connected to a compressor inlet pipe 34 connected to the refrigerant inlet 18 a of the compressor 18. Therefore, the refrigerant from the first evaporator 26 and the refrigerant from the second evaporator 28 return to the compressor 18.

  The air conditioning electronic control unit 16 is electrically connected to the engine electronic control unit 35 of FIG. 1 provided in the vehicle. The air conditioning electronic control device 16 and the engine electronic control device 35 are composed of a well-known microcomputer composed of a CPU, ROM, RAM, and the like and peripheral circuits thereof. Execute control processing. The air conditioning electronic control device 16 corresponds to the control device of the present invention.

  Various signals are transmitted and received between the air conditioning electronic control device 16 and the engine electronic control device 35. For example, from the engine electronic control device 35 to the air conditioning electronic control device 16, a signal indicating the rotational speed of the engine 12, a signal indicating the vehicle speed, and the idling stop control executed by the engine electronic control device 35 are being executed. A signal or the like representing is input. On the other hand, a signal for instructing the engine 12 to start is input from the air conditioning electronic control device 16 to the engine electronic control device 35.

  The engine electronic control unit 35 comprehensively controls the fuel injection amount, the ignition timing, and the like to the engine 12 based on signals from a sensor group (not shown) that detects the operating state of the engine 12 as is well known. It is. Further, the engine electronic control unit 35 executes the idling stop control described above when a predetermined idling stop condition is satisfied, for example, when the brake pedal is depressed and the vehicle is stopped. If the idling stop condition is not satisfied during the execution of the idling stop control, the engine 12 is restarted and the idling stop control is terminated.

  The air conditioning electronic control device 16 executes various air conditioning controls in the passenger compartment. For example, the inside / outside air suction control for switching the air sucked by the blower of the vehicle air conditioner 10 to the inside air or the outside air, the air volume control for controlling the air volume blown into the vehicle interior, and the temperature of the air blown into the vehicle interior are controlled. Temperature control to be performed, blowout mode control for switching the air blowout port, and the like are executed.

  As shown in FIG. 1, various detection signals or operation signals are input to the air conditioning electronic control device 16 from known sensors or operation switches. For example, a signal from the first evaporator temperature sensor 32 that detects the first evaporator temperature Te1, a signal from the rear seat sensor 36 that detects that an occupant is seated in the rear seat, and an outside air that detects the outside air temperature Tam. A signal from the temperature sensor 38, a signal from the solar radiation sensor 40 for detecting the amount of solar radiation Ts into the passenger compartment, a signal from an inside air temperature sensor (not shown) for detecting the inside air temperature, and a passenger in the front seat are operated. A signal from the front seat operating air conditioner switch 42, a signal from the rear seat operating air conditioner switch 44 arranged to be operated by a passenger in the rear seat, a signal from an air conditioning operation switch other than the switches 42, 44, etc. Entered. The rear seat seating sensor 36 corresponds to the second seat seating sensor in the present invention.

  The sensors 32, 36, 38, 40 and the operation switches 42, 44 described above are all well known. For example, the solar radiation sensor 40 shown in FIG. 1 is provided in the vicinity of the windshield in the vehicle interior, and detects the solar radiation amount Ts of the sunlight inserted into the vehicle interior.

  The front seat operation air conditioner switch 42 is provided at a position where the front seat passenger can easily operate in the passenger compartment. The front seat operation air conditioner switch 42 is a switch for turning on / off the air conditioning of the vehicle interior space around the front seat and the air conditioning of the vehicle interior space around the rear seat. In other words, the front seat operation air conditioner switch 42 is a switch for driving the compressor 18 for air conditioning of the vehicle interior space around the front seat or air conditioning of the vehicle interior space around the rear seat. For example, in the air conditioning switch 42 for front seat operation, air conditioning is turned on and off independently for each of the vehicle interior space around the front seat and the vehicle interior space around the rear seat.

  The rear seat operation air conditioner switch 44 is provided at a position where the passenger in the rear seat can easily operate in the vehicle interior, and is a switch for turning on / off the air conditioning of the vehicle interior space around the rear seat. In other words, the rear seat operation air conditioner switch 44 is a switch for driving the compressor 18 for air conditioning of the vehicle interior space around the rear seat. The front seat operation air conditioner switch 42 and the rear seat operation air conditioner switch 44 correspond to the air conditioner switch in the present invention.

  Next, control processing executed by the air conditioning electronic control device 16 in the present embodiment will be described. The air conditioning electronic control device 16 is activated when the vehicle ignition switch is turned on, and the air conditioning by the vehicle air conditioning device 10 is turned on by the front seat operation air conditioner switch 42 or the rear seat operation air conditioner switch 44. Then, the control process shown in the flowchart of FIG. 2 is periodically executed.

  First, in S110 of FIG. 2, it is determined whether or not the idling stop control is being executed in the vehicle, that is, whether or not the engine 12 is being automatically stopped. Specifically, when a signal indicating that the idling stop control is being executed is input from the engine electronic control device 35, it is determined that the idling stop control is being executed. If it is determined in S110 that the engine 12 is being automatically stopped, the steps after S120 are executed.

  In step S120, the outside air temperature sensor 38 detects the outside air temperature Tam. Subsequently, in S130, it is determined whether or not there is a backseat boarding, that is, whether or not the occupant is in the backseat. Specifically, whether or not the passenger is in the rear seat is determined based on a signal from the rear seat seating sensor 36. That is, when the rear seat seating sensor 36 detects that an occupant is seated in the rear seat, it is determined that the occupant is in the rear seat. More specifically, the rear seat has a plurality of seating locations, and a rear seat seating sensor 36 is provided at each of the seating locations. Then, when the rear seat seating sensor 36 detects that the occupant is seated in at least one of the plurality of seating locations in the rear seat, it is determined that the occupant is in the rear seat.

  If it is determined in S130 that the occupant is in the rear seat, the process proceeds to S150. On the other hand, if it is determined that the passenger is not in the rear seat, the process proceeds to S140.

  In S140, an evaporator temperature threshold value Tex to be compared with the first evaporator temperature Te1 is set based on the outside air temperature Tam from the relationship indicated by the solid line L01 in FIG. On the other hand, in S150, the evaporator temperature threshold value Tex is set based on the outside air temperature Tam from the relationship indicated by the solid line L02 in FIG.

  That is, in both S140 and S150, it is common to set the evaporator temperature threshold value Tex. However, in S140, the evaporator temperature threshold value Tex is set under the condition that the passenger is not in the rear seat, and in S150, the evaporator temperature threshold value Tex is set under the condition that the passenger is in the rear seat. Set. In short, the evaporator temperature threshold value Tex is set to a different value depending on whether or not the occupant is in the rear seat.

  Specifically, the relationship between the outside air temperature Tam and the evaporator temperature threshold value Tex as shown in FIG. 3 is tested in advance for each of the case where the passenger is in the rear seat and the case where the passenger is not in the rear seat. Is stipulated. In S140 and S150, the evaporator temperature threshold value Tex is set from the predetermined relationship shown in FIG. 3 based on the outside air temperature Tam detected in S120.

  As shown in FIG. 3, the relationship between the outside air temperature Tam and the evaporator temperature threshold value Tex when the passenger is not in the rear seat is represented by a solid line L01. The relationship indicated by the solid line L01 indicates that, even when the occupant is not in the rear seat, the front passenger is normally in the occupant, so the comfort of the occupant in the front seat is determined solely by the idling stop control. The evaporator temperature threshold value Tex is set in advance so that it is maintained in the stopped state and is set to the highest possible temperature. Further, the higher the outside air temperature Tam, the higher the cooling capacity is required. Therefore, in the relationship indicated by the solid line L01, the higher the outside air temperature Tam, the lower the evaporator temperature threshold Tex.

  Further, the relationship between the outside air temperature Tam and the evaporator temperature threshold value Tex when the passenger is in the rear seat is represented by a solid line L02. When the occupant is in the rear seat, the occupant is also in the front seat, so the relationship indicated by the solid line L02 indicates that the comfort of the occupant in the front seat and the rear seat is compressed by the idling stop control. It is predetermined that the evaporator temperature threshold value Tex is set to be as high as possible and maintained when the machine 18 is stopped.

  Here, the first evaporator 26 for front seat side air conditioning is provided with the cold storage material 30, but the second evaporator 28 for rear seat side air conditioning is not provided with the cold storage material 30, so the compressor 18 is stopped. In this case, the temperature of the second evaporator 28 is more likely to rise than that of the first evaporator 26. Therefore, the relationship indicated by the solid line L02 is, in other words, the temperature Te2 of the second evaporator 28, that is, the temperature of the second evaporator 28, that is, the evaporator temperature threshold value Tex is equal to or lower than the temperature that can ensure the comfort of the passengers in the rear seat. It is determined in advance so as to be set to a value that can suppress Te2.

  Therefore, the relationship indicated by the solid line L02 is indicated by the solid line L01 so that the comfort of the passenger can be maintained not only by the conditioned air that has passed through the first evaporator 26 but also by the conditioned air that has passed through the second evaporator 28. The evaporator temperature threshold value Tex is set to be lower than that in the relationship. That is, from the relationship of FIG. 3, the evaporator temperature threshold value Tex is set lower when the passenger is in the rear seat than when the passenger is not in the rear seat.

  For example, as shown in FIG. 3, in the relationship indicated by the solid line L02, the evaporator temperature threshold value Tex is set lower by a predetermined value α than the relationship indicated by the solid line L01. The predetermined value α may be constant regardless of the outside air temperature Tam, or may be a different value depending on the outside air temperature Tam. In addition, maintaining passenger comfort is, for example, suppressing unpleasant heat for the passenger, and suppressing smell generated when the condensed water adhering to the evaporators 26 and 28 dries. Also in the relationship indicated by the solid line L02, as with the solid line L01, the higher the outside air temperature Tam, the lower the evaporator temperature threshold Tex.

  When the evaporator temperature threshold value Tex is set in S140 or S150 shown in FIG. 2, the process proceeds to S160. In S160, the first evaporator temperature sensor 32 detects the first evaporator temperature Te1. Subsequently, in S170, it is determined whether or not the first evaporator temperature Te1 detected in S160 is equal to or higher than the evaporator temperature threshold Tex.

  If it determines with 1st evaporator temperature Te1 being more than the evaporator temperature threshold value Tex in S170, it will progress to S180. In S180, the engine 12 is started. Specifically, a signal instructing start of the engine 12 is output to the engine electronic control unit 35. Then, engine electronic control unit 35 starts engine 12 in accordance with a signal instructing start of engine 12. That is, the idling stop control is terminated. Then, when the engine 12 is started, the compressor 18 interlocked with the engine 12 is started.

  When the engine 12 is started in S180, the process returns to S110. In S110 after starting the engine 12 in S180, it is determined that the idling stop control is not being executed because the engine 12 is being driven.

  On the other hand, if it determines with 1st evaporator temperature Te1 being less than the evaporator temperature threshold value Tex in S170, it will return to S110, without passing through S180. Accordingly, the control process shown in the flowchart of FIG. 2 is repeatedly executed unless the idling stop control is terminated by, for example, a start operation of the vehicle by the occupant.

  Note that the processing in each step of FIG. 2 described above constitutes a means for realizing each function. The same applies to the flowcharts of FIGS. 7 and 9 described later.

  Next, the control processing shown in the flowchart of FIG. 2 will be described using the time charts shown in FIGS. 4 and 5. FIG. 4 is a time chart when the occupant is not in the back seat. That is, it is a time chart when it is determined in S130 of FIG. 2 that the passenger is not in the rear seat and S140 is executed. On the other hand, FIG. 5 is a time chart when the occupant is in the rear seat. That is, it is a time chart when it is determined in S130 of FIG. 2 that the occupant is in the rear seat and S150 is executed. In the time charts of FIGS. 4 and 5, the outside air temperature Tam is the same as each other.

  4 and 5, the time point t1 represents the time point when the vehicle speed becomes zero and the vehicle stops. Accordingly, the idling stop control is started from time t1, and the engine 12 and the compressor 18 are switched from the drive state to the stop state at time t1. Therefore, from the time point t1, the cooling in the first evaporator 26 and the second evaporator 28 stops, and the first evaporator temperature Te1 and the second evaporator temperature Te2 are starting to rise. From time t1, it is determined in S110 that idling stop control is being executed.

  4 and 5, the first evaporator temperature Te1 has reached the evaporator temperature threshold value Tex. Accordingly, S180 in FIG. 2 is executed at time t2, and the engine 12 and the compressor 18 are started. That is, the idling stop control is completed at time t2. Since the compressor 18 is driven from the time t2 and the first evaporator 26 and the second evaporator 28 are cooled by the refrigerant, the first evaporator temperature Te1 and the second evaporator temperature Te2 are decreased from the time t2. .

  Here, in the time chart of FIG. 4, since it is determined in S130 of FIG. 2 that the passenger is not in the rear seat, the evaporator temperature threshold Tex is set from the relationship indicated by the solid line L01 of FIG. The evaporator temperature threshold value Tex is represented in FIG. 4 as a broken line Lx1. On the other hand, in the time chart of FIG. 5, since it is determined in S130 of FIG. 2 that the passenger is in the rear seat, the evaporator temperature threshold Tex is set from the relationship indicated by the solid line L02 of FIG. The evaporator temperature threshold value Tex is represented in FIG. 5 as a broken line Lx2. For comparison with the broken line Lx2, the broken line Lx1 in FIG. 4 is also displayed in FIG. 5, and the evaporator temperature threshold value Tex indicated by the broken line Lx2 is set to a temperature lower than the broken line Lx1 by a predetermined value α. ing. The predetermined value α in FIG. 5 is the same as that in FIG.

  As can be seen from the definition of the evaporator temperature threshold value Tex described above, the evaporator temperature threshold value Tex indicated by the broken line Lx1 is the first evaporator 26 that does not impair the comfort of the passenger in the front seat when the passenger is in the front seat. Is the upper limit temperature. Further, since the temperature at which the passenger feels uncomfortable whether in the front seat or the rear seat does not change, the evaporator temperature threshold Tex indicated by the broken line Lx1 is the comfort of the passenger in the rear seat when the passenger is in the rear seat. It is also the upper limit temperature of the second evaporator 28 that does not impair the temperature.

  Moreover, since the 1st evaporator 26 is provided with the cool storage material 30 and the 2nd evaporator 28 is not provided with the cool storage material 30, in FIG.4 and FIG.5, it is the 2nd evaporator from the time t1 to the time t2. The temperature Te2 has risen to a temperature higher than the first evaporator temperature Te1. In the time chart of FIG. 4, the second evaporator temperature Te2 exceeds the temperature indicated by the broken line Lx1 at the time t2, but the occupant is not in the rear seat and the comfort of the occupant in the front seat is As long as it is ensured, passenger comfort is ensured. Further, in the time chart of FIG. 5, the occupant is in the rear seat, and it is necessary to ensure the comfort of not only the front seat occupant but also the rear seat occupant. All the evaporator temperatures Te2 are kept below the temperature indicated by the broken line Lx1, and passenger comfort is ensured.

  Here, in the time chart of FIG. 5, since the second evaporator 28 has a lower ability to store cold than the first evaporator 26, the second evaporator temperature Te2 is higher than the first evaporator temperature Te1 from time t1 to time t2. Is also high. If the ability of the second evaporator 28 to store cold is lower than that of the first evaporator 26, for example, the temperature difference between the first evaporator temperature Te1 and the second evaporator temperature Te2 increases. That is, the temperature difference between the broken line Lx1 and the broken line Lx2 further increases.

  Therefore, in order to ensure the comfort of passengers, the relationship shown in FIG. 3 is that the predetermined value α shown in FIGS. 3 and 5 increases as the ability of the second evaporator 28 to store cold is lower than that of the first evaporator 26. It is set in advance so that Therefore, the difference between the evaporator temperature threshold value Tex set when the passenger is in the rear seat and the evaporator temperature threshold value Tex set when the passenger is not in the rear seat is the cold storage of the second evaporator 28. The ability to perform is lower than that of the first evaporator 26, so that it is expanded. In other words, the evaporator temperature threshold value Tex set when the passenger is in the rear seat is based on the case where the passenger is not in the rear seat. The lower the vessel 26, the lower it becomes.

  Since the evaporator temperature threshold value Tex indicated by the broken line Lx2 is a temperature lower than the broken line Lx1, as can be seen by comparing FIG. 4 and FIG. 5, the possible engine stop time from the time point t1 to the time point t2 is as shown in FIG. The time chart is shorter than FIG.

  The vehicle is started at time t3 in FIGS. 4 and 5, and the vehicle speed that has been zero until time t3 increases at time t3.

  In addition, the stop time from the time t1 to the time t3 is the same between FIG. 4 and FIG. Further, the first evaporator temperature Te1 at time t1 is the same between FIG. 4 and FIG. 5, and the second evaporator temperature Te2 at time t1 is also the same between FIG. 4 and FIG.

  As described above, according to the present embodiment, the engine 12 that is the power source of the compressor 18 has the first evaporator temperature Te1 set to the evaporator temperature threshold Tex during the idling stop control, that is, during the automatic stop of the engine 12. It starts when it becomes above. And since the evaporator temperature threshold value Tex is set to a different value depending on whether or not an occupant is in the rear seat, the case where the occupant is in the rear seat and the case in which the occupant is not in the rear seat In any case, it is possible to maintain the comfort of the occupant while not unnecessarily shortening the time during which the engine 12 is automatically stopped.

  Further, according to the present embodiment, since it is the first evaporator temperature Te1 that is compared with the evaporator temperature threshold value Tex in S170 of FIG. 2, it is necessary to detect the second evaporator temperature Te2 with a temperature sensor or the like. There is no advantage.

  Further, according to the present embodiment, as shown in FIG. 3, the evaporator temperature threshold value Tex is set lower when the passenger is in the rear seat than when the passenger is not in the rear seat. Taking into account the fact that the second evaporator 28 has a lower ability to store cold than the first evaporator 26 depending on the presence or absence of the cold storage material 30, the duration of idling stop control is increased while ensuring passenger comfort. Is possible.

  Further, according to the present embodiment, as shown in FIG. 3, the evaporator temperature threshold value Tex is set to be lower as the outside air temperature Tam is higher, so that passenger comfort is ensured in a wide range of outside air temperature Tam. It is possible to lengthen the duration of idling stop control.

  Further, in a vehicle, the frequency of occupants in the front seat is usually higher than in the rear seat, and according to the present embodiment, the regenerator 30 is provided in the first evaporator 26 for air conditioning on the front seat side. During the idling stop control, it is possible to suppress the temperature rise of the first evaporator 26 that is frequently used to ensure the comfort of the passenger.

(Second Embodiment)
Next, a second embodiment of the present invention will be described. In the present embodiment, differences from the first embodiment will be mainly described, and the same or equivalent parts as those in the first embodiment will be omitted or simplified. The same applies to a third embodiment described later.

  FIG. 6 is a schematic diagram showing an overall configuration of the vehicle air conditioner 10 according to the second embodiment of the present invention. As shown in FIG. 6, the vehicle air conditioner 10 of the present embodiment differs from the first embodiment described above in that the refrigeration cycle 14 includes an on-off valve 60.

  The on-off valve 60 is provided in a refrigerant flow path 62 between the refrigerant outlet 28 a of the second evaporator 28, the refrigerant outlet 26 a of the first evaporator 26, and the compressor inlet pipe 34. Open and close. The on-off valve 60 is, for example, an electromagnetic valve that operates in response to a command signal from the air conditioning electronic control device 16.

  Next, control processing executed by the air conditioning electronic control device 16 of the present embodiment will be described. The air-conditioning electronic control device 16 periodically executes the control process shown in the flowchart of FIG. 7 in the same manner as in the first embodiment. FIG. 7 is a flowchart corresponding to FIG. 2 described above, and differs from FIG. 2 in that S141, S151, S171, and S191 are provided. 7, steps having the same contents as those in FIG. 2 are denoted by the same reference numerals and description thereof is omitted.

  In the flowchart of FIG. 7, the process proceeds to S141 after S140. In S141, the on-off valve 60 is closed and the refrigerant flow path 62 is shut off. Further, after S150, the process proceeds to S151. In S151, the on-off valve 60 is opened, and the refrigerant flow path 62 is brought into a communication state.

  That is, when it is determined in S130 that the occupant is in the rear seat while the engine 12 is automatically stopped, the on-off valve 60 is opened while it is determined in S130 that the occupant is not in the rear seat. Closes the on-off valve 60.

  When the on-off valve 60 is closed in S141, the compressor 18 connected to the refrigerant outlet 26a of the first evaporator 26 together with the on-off valve 60 is stopped, so that the refrigerant outlet 26a of the first evaporator 26 is Blocked. Further, since the first expansion valve 22 connected to the refrigerant inlet 26b of the first evaporator 26 prevents the refrigerant from flowing when the compressor 18 is stopped, the first expansion valve 22 causes the refrigerant of the first evaporator 26 to flow. The inlet 26b is closed. Therefore, when the on-off valve 60 is closed in S <b> 141, the refrigerant in the first evaporator 26 is confined in the first evaporator 26. The process following S141 proceeds to S160, and the process subsequent to S151 also proceeds to S160.

  In the flowchart of FIG. 7, if it is determined in S170 that the first evaporator temperature Te1 is equal to or higher than the evaporator temperature threshold Tex, the process proceeds to S171. In S171, the on-off valve 60 is opened. This is because the refrigerant can be circulated to the second evaporator 28 when the compressor 18 is started in S180. After S171, the process proceeds to S180.

  In the flowchart of FIG. 7, when it is determined in S110 that the engine 12 is not automatically stopped, the process proceeds to S191. In S191, the on-off valve 60 is opened, and the refrigerant flow path 62 is brought into a communication state. For example, in S191, when the on-off valve 60 is already open, the open state is maintained. On the other hand, if the idling stop control is terminated due to depression of the accelerator pedal or the like after closing the on-off valve 60 in S141, the on-off valve 60 is switched from the closed state to the open state in S191. .

  Note that the relationship between the outside air temperature Tam in FIG. 3 and the evaporator temperature threshold value Tex used in S140 and S150 of the present embodiment is the same as in the first embodiment described above.

  Next, in the time chart of this embodiment, a different point from the first embodiment will be described. The time chart when the passenger is not in the rear seat is FIG. 4 in the first embodiment, but is shown in FIG. 8 in the present embodiment. On the other hand, the time chart when the occupant is in the rear seat is the same as FIG. 5 in the present embodiment as in the first embodiment. This is because when the occupant is in the rear seat, the on-off valve 60 is opened and the circuit through which the refrigerant flows is the same as in the first embodiment.

  The time points t1 to t3 shown in FIG. 8 mean the same time points as in FIG. That is, time t1 represents the time when the vehicle stopped, time t2 represents the time when the first evaporator temperature Te1 reached the evaporator temperature threshold Tex, and time t3 represents the time when the vehicle was started.

  Although not shown in FIG. 8, at time t <b> 1, it is determined in S <b> 110 of FIG. 7 that the idling stop control is being executed, and it is determined in S <b> 130 that the occupant is not in the rear seat, In S141, the on-off valve 60 is closed. At time t2, since it is determined in S170 of FIG. 7 that the first evaporator temperature Te1 is equal to or higher than the evaporator temperature threshold value Tex, the on-off valve 60 is opened in S171.

  Here, when the on-off valve 60 of the refrigerant flow path 62 is opened or when the on-off valve 60 is not provided, the refrigerant outlet 26 a of the first evaporator 26 and the refrigerant outlet 28 a of the second evaporator 28. And communicate with each other. Then, the first evaporator 26 and the second evaporator 28 are in communication with each other. Therefore, during the execution of the idling stop control, the refrigerant in the first evaporator 26 and the refrigerant in the second evaporator 28. So that the temperature of the refrigerant changes so as to approach each other and the pressure equalization that changes so that the pressures of the refrigerants approach each other are likely to occur. That is, the cool storage material 30 suppresses not only the first evaporator 26 but also the temperature rise of the second evaporator 28.

  On the other hand, when the on-off valve 60 is closed, the above temperature equalization and pressure equalization are unlikely to occur, so the regenerator 30 exclusively suppresses the temperature rise of the first evaporator 26. .

  4 and FIG. 8, the regenerator 30 is provided only in the first evaporator 26, so that the first evaporator temperature Te1 is the second evaporator from the time t1 to the time t2. The temperature is lower than Te2.

  Therefore, since the on-off valve 60 is closed in FIG. 8 from the time point t1 to the time point t2, the rising gradient of the first evaporator temperature Te1 is smaller than that in FIG. On the other hand, the rising gradient of the second evaporator temperature Te2 is larger than that in FIG. That is, the difference between the rising gradient of the first evaporator temperature Te1 and the rising gradient of the second evaporator temperature Te2 when the occupant is not in the rear seat from the time point t1 to the time point t2 (see FIG. 8). ) Is larger than the difference Bds (see FIG. 5) between the rising gradient of the first evaporator temperature Te1 and the rising gradient of the second evaporator temperature Te2 when the occupant is in the rear seat.

  In the present embodiment described above, the same effects as those in the first embodiment described above can be obtained. Furthermore, according to the present embodiment, the on-off valve 60 is provided in the refrigerant flow path 62 between the first evaporator 26 and the second evaporator 28. During the automatic stop of the engine 12, the on-off valve 60 is Since the rear seat is closed when no passenger is in the vehicle, the latent heat of the regenerator 30 provided in the first evaporator 26 can be used intensively to suppress the rise in the first evaporator temperature Te1. It is. Therefore, during the automatic stop of the engine 12, the time until the first evaporator temperature Te1 reaches the evaporator temperature threshold value Tex is increased, and the time during which the engine 12 can be automatically stopped, that is, the time during which the idling stop control can be continued is increased. Is possible.

  On the other hand, when the engine 12 is automatically stopped, the on-off valve 60 is opened when an occupant is in the rear seat, so that the refrigerant is balanced between the first evaporator 26 and the second evaporator 28. Using the latent heat of the regenerator 30 provided in the first evaporator 26 not only for suppressing the rise of the first evaporator temperature Te1 but also for suppressing the rise of the second evaporator temperature Te2 by warming and equalizing pressure. Is possible.

(Third embodiment)
Next, a third embodiment of the present invention will be described. The refrigeration cycle 14 of this embodiment is the same as that of the first embodiment shown in FIG. In the present embodiment, the control processing performed by the air conditioning electronic control device 16 is partially different from that in FIG. 2 of the first embodiment. FIG. 9 shows a flowchart for explaining a control process performed by the air conditioning electronic control device 16 of the present embodiment.

In the flowchart of FIG. 9, S121 is added to FIG. 2 and replaced from S140 to S142 and replaced from S150 to S152. In S <b> 121 of FIG. 9, the solar radiation amount Ts is detected by the solar radiation sensor 40. The unit of the solar radiation amount Ts is, for example, W / m ² . After S121, the process proceeds to S130.

  In S142, instead of the solid line L01 in FIG. 3, the evaporator temperature based on the outside air temperature Tam and the solar radiation amount Ts detected in S121 based on the relationship between the outside air temperature Tam and the evaporator temperature threshold value Tex shown in FIG. A threshold Tex is set. In S152, instead of the solid line L02 in FIG. 3, the relationship between the outside air temperature Tam and the evaporator temperature threshold Tex shown in FIG. 10B is used to evaporate based on the outside air temperature Tam and the solar radiation amount Ts detected in S121. Set the vessel temperature threshold Tex.

  FIGS. 10A and 10B show the relationship between the outside air temperature Tam and the evaporator temperature threshold value Tex, which is preset according to the solar radiation amount Ts. FIG. 10A is used when the occupant is not in the rear seat, and FIG. 10B is used when the occupant is in the rear seat.

  FIG. 10A corresponds to the solid line L01 of FIG. 3 in the first embodiment, and is experimentally determined in the same manner as the solid line L01. FIG. 10B corresponds to the solid line L02 of FIG. 3 in the first embodiment, and is experimentally determined in the same manner as the solid line L02. However, FIGS. 10A and 10B differ from FIG. 3 in that the solar radiation amount Ts is added as a parameter for setting the evaporator temperature threshold value Tex.

  10A and 10B, the evaporator temperature threshold value Tex is lower as the outside air temperature Tam is higher, as in FIG. Further, in order to ensure passenger comfort, the higher the solar radiation amount Ts, the higher the cooling capacity is required. Therefore, the larger the solar radiation amount Ts, the lower the evaporator temperature threshold Tex. Similar to the mutual relationship between the solid line L01 and the solid line L02 in FIG. 3, the relationship between the outside air temperature Tam and the evaporator temperature threshold value Tex corresponding to the solar radiation amount Ts shown in FIG. Compared to (a), the evaporator temperature threshold value Tex is set lower by a predetermined value α. Similarly to FIG. 3, in any of FIGS. 10A and 10B, when the outside air temperature Tam changes, the change width of the evaporator temperature threshold Tex is smaller than the change width of the outside air temperature Tam. .

  In the present embodiment described above, the same effects as those in the first embodiment described above can be obtained. Furthermore, according to the present embodiment, as shown in FIGS. 10A and 10B, the evaporator temperature threshold value Tex is set to be lower as the solar radiation amount Ts is larger. Therefore, in the wide range of the solar radiation amount Ts, It is possible to lengthen the duration of idling stop control while ensuring comfort.

(Other embodiments)
(1) In the above-described embodiment, the temperature detected by the first evaporator temperature sensor 32 is the first evaporator temperature Te1 compared with the evaporator temperature threshold value Tex, but the first evaporator temperature Te1 is the first evaporator temperature Te1. Any physical quantity that has a strong correlation with the cooling capacity of one evaporator 26 may be used. For example, as shown in FIG. 11, an air temperature sensor 70 is provided immediately after the air flow downstream side of the first evaporator 26, and immediately after the air flow downstream of the first evaporator 26 detected by the air temperature sensor 70. The air temperature may be detected as the first evaporator temperature Te1.

  (2) In the above embodiment, the refrigeration cycle 14 has two evaporators, the first evaporator 26 and the second evaporator 28, but the refrigeration cycle 14 includes three or more evaporators. There is no problem.

  (3) In the above-described embodiment, as shown in FIGS. 3 and 10, the evaporator temperature threshold value Tex is set lower when the occupant is in the rear seat than in the case where the occupant is not in the rear seat. However, depending on disturbances such as the amount of solar radiation around the front seat and the rear seat, the evaporator temperature threshold Tex is on the back seat when the passenger is on the back seat. It may be set higher than the case where it is not. Further, the magnitude relationship of the evaporator temperature threshold value Tex may be reversed between a case where an occupant is in the rear seat and a case where the passenger is not in the rear seat, with a certain outside air temperature Tam as a boundary.

  (4) In the above-described embodiment, the vehicle includes a front seat and a rear seat, but may further include a seat in addition to them.

  (5) In the above-described embodiment, the compressor 18 is mechanically connected to the engine 12. However, if the compressor 18 is also stopped when the engine 12 stops, the compressor 18 is mechanically connected to the engine 12. It does not matter if it is not.

  (6) In the above-described embodiment, as shown in FIGS. 3 and 10, the evaporator temperature threshold value Tex is set based on the outside air temperature Tam, but may be set regardless of the outside air temperature Tam.

  (7) In the third embodiment described above, as shown in FIG. 10, the evaporator temperature threshold Tex is set based on the outside air temperature Tam and the amount of solar radiation Ts, but the amount of solar radiation is independent of the outside air temperature Tam. It may be set based on Ts, or may be set based on a physical quantity other than the outside air temperature Tam and the solar radiation amount Ts. Alternatively, it may be always a constant value.

  (8) In the above embodiment, in S110 of the flowcharts of FIGS. 2, 7, and 9, it is determined whether or not the idling stop control is being executed, that is, whether or not the engine 12 is being automatically stopped. However, the automatic stop of the engine 12 is not limited to the idling stop control. For example, the engine 12 may be automatically stopped when the hybrid vehicle is running.

  (9) In the above-described embodiment, the second evaporator 28 is not provided with a temperature sensor for detecting the temperature thereof. A temperature sensor for detecting the temperature of the vessel 28 may be provided.

  (10) In the above-described embodiment, whether or not the occupant is in the rear seat is determined based on a signal from the rear seat seating sensor 36 in S130 of FIGS. The determination may be made based on an operation signal from the front seat operation air conditioner switch 42 or the rear seat operation air conditioner switch 44. In this case, when the air conditioning of the vehicle interior space around the rear seat is turned on by the switch operation of the front seat operation air conditioner switch 42 or the rear seat operation air conditioner switch 44, Is determined to be on board.

  (11) In the above-described second embodiment, S180 is executed after S171 in the flowchart of FIG. 7, but the order of S171 and S180 may be reversed.

  (12) In the above-described embodiment, the air conditioning electronic control device 16 and the engine electronic control device 35 are configured as separate control devices, but the air conditioning electronic control device 16 and the engine electronic control device 35 May constitute one control device as a unit.

  (13) In the above-described embodiment, the processing of each step shown in the flowcharts of FIGS. 2, 7, and 9 is realized by a computer program, but may be configured by hard logic. Absent.

  In addition, this invention is not limited to above-described embodiment, In the range described in the claim, it can change suitably. Further, the above embodiments are not irrelevant to each other, and can be combined as appropriate unless the combination is clearly impossible. For example, if the third embodiment is combined in the second embodiment, the evaporator temperature threshold value Tex is set using the predetermined relationship of FIG. 10 instead of FIG.

  In each of the above-described embodiments, it is needless to say that elements constituting the embodiment are not necessarily essential unless explicitly stated as essential and clearly considered essential in principle. Yes. Further, in each of the above embodiments, when numerical values such as the number, numerical value, quantity, range, etc. of the constituent elements of the embodiment are mentioned, it is clearly limited to a specific number when clearly indicated as essential and in principle. The number is not limited to the specific number except for the case. Further, in each of the above embodiments, when referring to the shape, positional relationship, etc. of the component, etc., the shape, unless otherwise specified and in principle limited to a specific shape, positional relationship, etc. It is not limited to the positional relationship or the like.

DESCRIPTION OF SYMBOLS 10 Vehicle air conditioner 12 Engine 14 Refrigeration cycle 16 Air-conditioning electronic control device (control device)
18 Compressor 26 First evaporator 28 Second evaporator 30 Cold storage material

Claims (11)

In a vehicle in which control for automatically stopping an engine (12) is performed, a vehicle air conditioner that air-conditions a vehicle interior including a first seat and a second seat of the vehicle,
A first evaporator (26) that is provided with a cold storage material (30) and that cools the air blown into the vehicle interior space around the first seat with a refrigerant in the refrigeration cycle (14);
A second evaporator (28) having a lower ability to store cold than the first evaporator, and cooling the air blown into the vehicle interior space around the second seat with the refrigerant;
A compressor (18) driven by the engine to compress and circulate the refrigerant in the refrigeration cycle;
The evaporator temperature threshold value (Tex) is set to a different value depending on whether or not an occupant is in the second seat, and the temperature (Te1) of the first evaporator is set during the automatic engine stop. A vehicle air conditioner comprising: a control device (16) for starting the engine when the temperature exceeds an evaporator temperature threshold value.   The said control apparatus sets the said evaporator temperature threshold value low when the passenger | crew is riding in the said 2nd seat compared with the case where it is not boarding | occupied to this 2nd seat. Vehicle air conditioner.   The vehicle air conditioner according to claim 1 or 2, wherein the first seat is a front seat and the second seat is a rear seat. An open / close valve (60) provided in the refrigerant flow path (62) between the first evaporator and the second evaporator to open and close the refrigerant flow path;
The vehicle according to any one of claims 1 to 3, wherein the control device closes the on-off valve when an occupant is not in the second seat during the automatic stop of the engine. Air conditioner.   5. The vehicle air conditioner according to claim 4, wherein the control device opens the on-off valve when the engine is started after the on-off valve is closed. 6. A first expansion valve (22) connected to the refrigerant inlet (26b) of the first evaporator in the refrigeration cycle;
The second evaporator is provided in parallel with the first evaporator and the first expansion valve in the refrigerant flow,
6. The vehicle according to claim 4, wherein the refrigerant flow path is a path that connects a refrigerant outlet (26 a) of the first evaporator and a refrigerant outlet (28 a) of the second evaporator. Air conditioner. A second seat seating sensor (36) for detecting that an occupant is seated in the second seat;
When the second seating sensor detects that an occupant is seated in the second seat, the control device determines that the occupant is in the second seat and sets the evaporator temperature threshold value. The vehicle air conditioner according to any one of claims 1 to 6, wherein the air conditioner is set. An air conditioner switch (42, 44) for turning on / off the air conditioning of the vehicle interior space around the second seat;
When the air conditioning of the vehicle interior space around the second seat is turned on by the operation of the air conditioner switch, the control device sets the evaporator temperature threshold as an occupant in the second seat. The vehicle air conditioner according to any one of claims 1 to 6, wherein the air conditioner is set.   The vehicle air conditioner according to any one of claims 1 to 8, wherein the control device sets the evaporator temperature threshold value lower as the outside air temperature (Tam) is higher.   The vehicle air conditioner according to any one of claims 1 to 8, wherein the control device sets the evaporator temperature threshold value lower as the amount of solar radiation (Ts) increases. The controller sets the evaporator temperature threshold such that the higher the outside air temperature (Tam) is, the lower the evaporator temperature threshold is, and the larger the amount of solar radiation (Ts) is, the lower the evaporator temperature threshold is. The vehicle air conditioner according to any one of claims 1 to 8.

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