JP2009138708A - Controller of vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a controller of an engine capable of reducing the consumption of a fuel while limiting the rise of the temperature inside a cabin when temporarily stopping the engine while a vehicle is stopped. <P>SOLUTION: This controller of a vehicle includes: a cabin temperature sensor 31 and an atmospheric temperature sensor 32 for detecting the temperature of the air supplied into an evaporator 12 by the operation of a blower fan 121; an evaporator temperature sensor 122 for detecting the temperature of the evaporator 12; and an engine stop time determination means 43 for determining an engine stop time according to the temperature detected by the evaporator temperature sensor 122 and the temperatures detected by the atmospheric temperature sensor 32 and the cabin temperature sensor 31 just before the stop of the engine 2. The engine control means 43 operates the blower fan 121 even after the engine 2 is stopped due to the establishment of stop conditions, and starts a compressor 6 by starting the engine 2 after the engine stop time is elapsed. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a vehicle control device that stops an engine when a stop condition is satisfied during operation of an engine mounted on the vehicle and starts the engine when a start condition is satisfied while the engine is stopped.

  2. Description of the Related Art Conventionally, there has been known a vehicle control device that suppresses fuel consumption by idling while the vehicle is stopped by temporarily stopping the engine while the vehicle is stopped (for example, Patent Documents). 1).

  In the vehicle control device described in Patent Document 1, the engine is stopped when the vehicle speed is zero, the vehicle is stopped, and the clutch switch is turned off (when the stop condition is satisfied). The engine is restarted when a predetermined time has elapsed since the start of the engine (when the start condition is satisfied).

In the vehicle control apparatus described in Patent Document 1, the predetermined time that is the engine start condition is set to a fixed time.
JP-A-4-358729

  When the vehicle interior is cooled by the operation of the engine, if the engine is stopped and the cooling is stopped, the temperature in the vehicle interior gradually increases. And when the time from engine stop to restart is made constant as in the vehicle control device described in Patent Document 1, for example, when the outside air temperature is high or the number of passengers is large, It is conceivable that the person who gets on the vehicle feels uncomfortable until the temperature suddenly rises and the engine is restarted and cooling is resumed.

  If the engine stop time is shortened in order to prevent such a situation, there is a disadvantage that the effect of reducing fuel consumption during idling is reduced.

  Therefore, the present invention provides an engine control device capable of reducing fuel consumption after limiting temperature rise in the passenger compartment when performing control to temporarily stop the engine while the vehicle is stopped. The purpose is to do.

  The present invention has been made to achieve the above object, and includes an engine, a blower fan that supplies air from outside the vehicle to the vehicle interior or circulates air in the vehicle interior, a refrigerant circulation path, and the refrigerant circulation path. A compressor that is connected and driven by the engine, and an evaporator that is connected to the refrigerant circulation path and is provided in a flow passage of air to the vehicle interior by the blower fan, the compressor and the Engine control means for stopping the engine when a predetermined stop condition is satisfied and starting the engine when a predetermined engine stop time elapses for a vehicle that operates the blower fan to cool the vehicle interior The present invention relates to a vehicle control apparatus provided.

  And a supply air temperature detecting means for detecting the temperature of air supplied to the evaporator by the operation of the blower fan, an evaporator temperature detecting means for detecting the temperature of the evaporator, and the evaporation immediately before the engine is stopped. Engine stop time determining means for determining the engine stop time based on the detected temperature of the detector temperature detecting means and the detected temperature of the supply air temperature detecting means, wherein the engine control means satisfies the stop condition. When the engine is stopped, the blower fan is operated even when the engine is stopped, and when the engine stop time has elapsed, the engine is started and the compressor is started.

  According to the present invention, when the stop condition is satisfied, the engine is stopped in a state where the compressor is operating, or in a state where not much time has passed since the compressor stopped operating. When the engine is stopped, the evaporator is in a low temperature state. Therefore, the cooling effect can be obtained to some extent by operating the blower fan after the engine is stopped and blowing air into the vehicle compartment via the evaporator. And the effect of such cooling becomes low as the temperature of the evaporator rises, and the rate of increase of the temperature of the evaporator becomes higher as the temperature of the air flowing around the evaporator becomes higher.

  Therefore, the engine stop time determining means determines the engine stop time based on the detected temperature of the evaporator temperature detecting means and the detected temperature of the supply air temperature detecting means immediately before the engine is stopped. As a result, the engine stop time can be determined by reflecting the degree of the cooling effect of the evaporator while the engine is stopped. Therefore, after limiting the temperature rise in the passenger compartment while the engine is stopped, Fuel consumption can be reduced.

  In the present invention, “immediately before stopping the engine” means that the difference between the detected temperature of the evaporator temperature detecting means immediately before the stop and the detected humidity of the evaporator temperature detected at the time of stopping the engine is minute (negligible). Level). When the engine is stopped, the compressor stops and the circulation of the refrigerant stops, so the temperature of the evaporator rises rapidly. For this reason, it is difficult to stably detect the temperature of the evaporator by the evaporator temperature detecting means, but by using the detected temperature immediately before the engine is stopped, the temperature of the evaporator when the engine is stopped can be stabilized. The engine stop time can be determined by detection (estimation).

  Further, vehicle condition detection means for detecting a situation where the vehicle is placed, and an allowable upper limit of the evaporator according to a target blowing temperature of air into the passenger compartment under the condition detected by the vehicle condition detection means An allowable upper limit temperature determining means for determining a temperature, wherein the engine stop time determining means increases the temperature difference between the detected temperature of the evaporator temperature detecting means and the allowable upper limit temperature immediately before the engine stops. The stop time is set to a long time.

  In the present invention, the temperature difference between the detected temperature of the evaporator temperature detecting means and the allowable upper limit temperature according to the target blowing temperature is a margin of a temperature rise in the vehicle compartment with respect to the target blowing temperature when the engine is stopped. It shows the degree. Therefore, the engine stop time determining means determines the engine stop time to be longer as the temperature difference is larger, thereby limiting the temperature rise in the passenger compartment while the engine is stopped to the vicinity of the target blow-off temperature. The fuel consumption of the engine can be reduced.

  Further, the engine stop time determining means determines the engine stop time to be shorter as the amount of air blown into the passenger compartment by the blower fan is larger.

  In this invention, since the flow rate of the air supplied to the evaporator increases as the amount of air blown into the passenger compartment by the blower fan increases, the rate of increase in the temperature of the evaporator increases. Therefore, by limiting the temperature increase in the vehicle compartment while the engine is stopped by determining the engine stop time to be shorter as the amount of air blown into the vehicle compartment is larger by the engine stop time determination means, The effect of reducing fuel stop can be enhanced.

  The engine stop time determining means may supply air outside the vehicle to the evaporator by the blower fan when air in the vehicle compartment is supplied to the evaporator by the blower fan while the engine is stopped. The engine stop time is set to a longer time than when the engine is stopped.

  In the present invention, when the passenger compartment is cooled by the operation of the compressor, it is considered that the outside air temperature is higher than the temperature in the passenger compartment. Therefore, the rate of temperature increase of the evaporator is higher when air outside the vehicle is supplied to the evaporator by the blower fan than when air inside the vehicle is supplied to the evaporator by the blower fan. Get higher. Therefore, when the engine stop time determining means supplies air in the vehicle compartment to the evaporator by the blower fan, the engine is more effective than when air outside the vehicle is supplied to the evaporator by the blower fan. By determining the stop time as a long time, it is possible to increase the effect of reducing fuel consumption while suppressing the temperature rise in the passenger compartment while the engine is stopped.

  Further, under the conditions detected by the vehicle condition detection means, a fog determination humidity estimation means for estimating a fog determination humidity that is a humidity at which the vehicle window glass does not fog, and humidity detection for detecting the humidity in the vehicle interior And the fogging occurrence estimation time, which is an estimated time until the window glass is fogged after the engine is stopped, as the humidity difference between the detection humidity of the humidity detection means and the fogging determination humidity immediately before the engine stops is larger, An estimated fog generation time determining means for determining a long time, and the engine control means stops the engine after the stop condition is satisfied and before the engine stop time elapses. When the estimated fog generation time has elapsed, the engine is started and the compressor is operated.

  According to the present invention, the fog determination humidity estimation means estimates the fog determination humidity which is a humidity at which the window glass does not fog under the situation detected by the vehicle situation detection means. The cloudy generation estimated time determining unit determines the cloudy generation estimated time to be longer as the humidity difference between the detected humidity of the humidity detecting unit and the cloudy determination humidity immediately before the engine is stopped is larger.

  Thus, the greater the difference in humidity between the fog determination humidity estimated according to the situation where the vehicle is placed and the detected humidity of the humidity detection means immediately before the engine is stopped, the longer the fog generation estimation time is. Thus, the estimated fog occurrence time can be determined by reflecting the ease of fogging of the window of the vehicle.

  Then, when the estimated fogging time elapses before the engine stop time elapses after the stop condition is satisfied and the engine is stopped by the engine control means, By starting the engine and operating the compressor, it is possible to prevent the window glass from fogging while the engine is stopped.

  An embodiment of the present invention will be described with reference to FIGS.

  FIG. 1 is a configuration diagram of a vehicle equipped with a vehicle control device of the present invention. The vehicle of the present embodiment is a hybrid vehicle that uses the engine 2 and the motor / generator G as drive sources, and when the vehicle stops waiting for a signal in order to reduce exhaust gas emissions and suppress fuel consumption, An engine stop / restart function is provided that stops the engine 2 when the stop condition is satisfied, and restarts the engine 2 when the start condition is satisfied, for example, when the vehicle is stopped during a traffic jam.

  In addition, the vehicle according to the present embodiment includes an air conditioner 1 that heats and cools the passenger compartment. The air conditioner 1 includes a cooling function and a dehumidifying function by the refrigeration cycle apparatus A, and a circulation path for the coolant of the engine 2. It has a heating function by the heater core H provided in B.

  The operations of the engine 2, the motor / generator G, and the air conditioner 1 are controlled by a control device 4 (corresponding to a vehicle control device of the present invention) that is an electronic unit composed of a microcomputer or the like. By executing a predetermined program, the control device 4 performs vehicle condition detection means 41, fog determination humidity estimation means 42, engine stop time determination means 43, engine control means 44, air conditioning control means 45, fog generation estimated time determination means. 46 and the allowable upper limit temperature determining means 47.

  The control device 4 includes a humidity sensor 30 for detecting the humidity in the vehicle interior (corresponding to the humidity detecting means of the present invention), an in-vehicle temperature sensor 31 for detecting the temperature in the vehicle interior, and an outside air temperature sensor 32 for detecting the temperature outside the vehicle. A solar radiation sensor 33 that detects the amount of solar radiation, a vehicle speed sensor 34 that detects the vehicle speed, and an evaporator temperature sensor 122 that detects the temperature in the vicinity of the downstream side of the evaporator 12 described later (corresponding to the evaporator temperature detecting means of the present invention). ) Is input. Further, the control device 4 receives operation signals from an air direction switch 35 that sets an air conditioning direction into the vehicle interior and an air conditioning switch 36 that sets air conditioning conditions (temperature, air volume, etc.).

  The operations of the engine 2, the motor / generator G, the air conditioner 1, and the like are controlled by a control signal output from the control device 4.

  The air conditioner 1 includes a compressor 6 driven by the engine 2, a condenser 9, a liquid receiver 10, an expansion valve 11, and an evaporator 12 as a configuration of the refrigeration cycle apparatus A. Further, as a configuration for heating, a heater core H constituting the coolant circulation path B of the engine 2, a water pump P driven by the engine 2, a thermostat Th, and a radiator R are provided.

  The engine 2 and the motor / generator G are directly connected to each other by a rotating shaft 21. With this configuration, it is possible to generate a driving force by the engine 2 and the motor / generator G and to generate regenerative power by the motor / generator G during deceleration. The rotation of the engine 2 and the motor / generator G is transmitted to the wheels W through the transmission Tr.

  Further, the motor / generator G has a function of a starter motor for starting the engine 2, and further, a battery 18 of the power storage device 17 (corresponding to a power storage unit of the present invention) by regenerative power of the motor / generator G. Is charged.

  Next, the refrigeration cycle apparatus A includes the compressor 6, the condenser 9, the liquid receiver 10, the expansion valve 11, and the evaporator 12, with the compressor 6 as the upstream side and the evaporator 12 as the downstream side. These are sequentially connected to the refrigerant circulation path 3. The refrigeration cycle evaporates, compresses, condenses, and expands refrigerant (made of chlorofluorocarbon, carbon dioxide, etc.).

  The air conditioning control means 45 of the control device 4 calculates the target evaporator temperature based on the temperature set by the air conditioning switch 36, the outside air temperature, the humidity, the amount of solar radiation, etc., and the target evaporator temperature and the evaporator temperature sensor 122. The compressor 6 is controlled so as to reduce the difference from the detected temperature. The compressor 6 is operated by the driving force of the engine 2, and the pulley 82 provided at the tip of the rotating shaft 81 of the engine 2, the pulley 85 provided on the driving shaft 84 of the compressor 6, and the pulleys 82, 85 are interlocked. The driving force of the engine 2 is transmitted to the compressor 6 by the belt 83 to be driven.

  Further, an electromagnetic clutch 86 is provided on the drive shaft 84 of the compressor 6, and the air conditioning control means 45 switches between transmission and interruption of the driving force of the engine 2 to the compressor 6 by the electromagnetic clutch 86.

  The condenser 9 cools and liquefies the refrigerant that has been compressed by the compressor 6 to a high temperature and high pressure by heat exchange. The liquid receiver 10 is a cylinder that temporarily stores the refrigerant liquefied by the condenser 9, and is connected to the expansion valve 11 via a dryer (not shown). Then, the refrigerant from which moisture has been removed by the dryer is supplied to the expansion valve 11.

  The expansion valve 11 is attached to the inlet side of the evaporator 12, and when the high-temperature and high-pressure liquefied refrigerant passes, the refrigerant is changed from a liquid to a mist-like gas and injected. The expansion valve 11 is provided with a throttle valve (not shown), and the air conditioning control means 45 controls the opening of the throttle valve to adjust the flow rate (refrigerant capacity) of the refrigerant injected into the evaporator 12. .

  The evaporator 12 is a heat exchanger that takes the heat of the air in the passenger compartment and cools it by vaporizing the refrigerant, and is accommodated in the air conditioning case 14. A blower fan 121 is provided on the upstream side of the evaporator 12, and the rotation speed of the blower fan 121 is controlled by the air conditioning control means 45. As the blower fan 121 rotates, the air dehumidified and cooled by the evaporator 12 and the air heated by the heater core H are blown into the vehicle interior, and the air or outside air in the vehicle interior is supplied to the air conditioning case 14. Air is sent into the vehicle compartment via the differential door 143, the vent door 144, and the floor door 145.

  Next, the configuration on the heating side will be described. The coolant of the engine 2 is supplied from the thermostat Th to the radiator R by a mechanical water pump P operated by the driving force of the engine 2 and circulates in the water jacket of the engine 2. Further, the coolant of the engine 2 is diverted to be used as a heat source for heating the passenger compartment, and flows through the circulation passage B that returns from the water pump P to the water pump P through the heater core H.

  The pulley 90 provided on the rotation shaft 81 of the engine 2, the pulley 92 provided on the drive shaft 94 of the water pump P <b> 1, and the belt 91 that interlocks the pulleys 90, 92 cause the driving force of the engine to be applied to the water pump P <b> 1. Communicated.

  The heater core H performs heat exchange for heating the surrounding air with the heat of the coolant heated by the engine 2 in the radiator R. On the upstream side of the heater core H, an air mix door 142 for guiding the air that has passed through the evaporator 12 to the heater core H side or bypassing it is installed.

  The air mix door 142 is composed of, for example, a rotary plate door that opens and closes the air inlet of the heater core H, and is opened and closed by an air mix servo motor (not shown) installed on the rotation center side. The air mix door 142 prevents air in the air conditioning case 14 from flowing into the heater core H when in the closed position a, and causes half of the air in the air conditioning case 14 to flow into the heater core H when in the intermediate position b. And the air in the air conditioning case 14 flows to the heater core H when in the release position c. The air conditioning control means 45 operates an air mix servo motor (not shown) to change the position of the air mix door 142, thereby controlling the temperature of air blown into the passenger compartment.

  The air conditioning case 14 is provided with an intake door 141 for switching between an inside air inlet and an outside air inlet on the upstream side, and air dehumidified and cooled by the evaporator 12 on the downstream side, or air heated by the heater core H A differential door 143 for discharging the water to the defroster, a vent door 144 for discharging the air to the ventilator, and a floor door 145 for discharging to the foot are installed. The intake door 141, the differential door 143, the vent door 144, and the floor door 145 may be electrically rotated by a servo motor or manually rotated.

  Next, stop / restart processing of the engine 2 by the engine control means 44 will be described according to the flowcharts shown in FIGS.

  The engine stop time determining means 43 repeatedly executes the flowcharts shown in FIGS. 2 to 3 when the engine 2 is operating, and within a temperature rise range in which the comfort in the passenger compartment can be maintained, and as much as possible. The engine stop time Ts is determined and updated in a long time.

  In STEP 1 of FIG. 2, the engine stop time determination means 43 determines whether or not the amount of air blown into the vehicle compartment by the blower fan 121 is set to “large” by the air conditioning switch 36. Then, when the blown air volume is set to “Large”, the process branches to STEP 20, and when it is not set to “Large”, the process proceeds to STEP2.

  In STEP 2, the engine stop time determining means 43 determines whether or not the blower fan 121 blown air volume into the vehicle interior is set to “small”. Then, when the blown air volume is set to “small”, the process branches to STEP 30, and when it is not set to “small”, the process proceeds to STEP3.

  If the outside air is set by the air conditioning switch 36 in STEP 3 (the intake door 141 is in a setting state in which outside air is introduced into the blower fan 121 from the outside air introduction port), the process branches to STEP 40. Then, in STEP 40, the engine stop time determining means 43 sets the temperature increase coefficient Kt of the evaporator 12 to K3, and proceeds to STEP 5 in FIG.

  On the other hand, if the inside air setting is set in STEP 3 by the air conditioning switch 36 (the intake door 141 is set to introduce the air in the vehicle compartment from the inside air inlet to the blower fan 121), the process proceeds to STEP 4. Then, the engine stop time determining means 43 sets the temperature increase coefficient Kt of the evaporator 12 to K4, and proceeds to STEP5 in FIG.

  Here, when the outside air is set, the temperature of the evaporator 12 is higher than that when the outside air is set because the outside air having a temperature higher than that in the passenger compartment is supplied to the evaporator 12. Therefore, K3 <K4 is set.

  If the outside air is set by the air conditioning switch 36 in STEP 20, the process branches to STEP 25. Then, in STEP 25, the engine control means 44 sets the temperature increase rate Kt of the evaporator 12 to K1, and proceeds to STEP 3 in FIG. On the other hand, when the inside air setting is set by the air conditioning switch 36 in STEP 20, the process proceeds to STEP 21. Then, the engine stop time determining means 43 sets the temperature increase coefficient Kt of the evaporator 12 to K2, and proceeds to STEP5 in FIG. Also in this case, K1 at the time of outside air setting is set to be larger (K2 <K1) than K2 at the time of inside air setting.

  If the outside air setting is set by the air conditioning switch 36 in STEP 30, the process branches to STEP 35. Then, in STEP 35, the engine control means 44 sets the temperature rise rate Kt of the evaporator to K5, and proceeds to STEP 5 in FIG. On the other hand, if the inside air setting is set by the air conditioning switch 36 in STEP 30, the process proceeds to STEP 31. Then, the engine stop time determining means 43 sets the temperature increase coefficient Kt of the evaporator 12 to K5, and proceeds to STEP5 in FIG.

  Here, as the amount of air blown into the passenger compartment increases, the flow rate of the air supplied to the evaporator 12 increases and the temperature increase rate of the evaporator 12 increases. Therefore, K1 to K5 are set to be larger for K3 and K4 when the blown air volume is medium than for K5 and K6 when the blown air volume is small, as shown in the following equation (1). K1 and K2 when the blown air volume is large are set larger.

K6 <K5 <K4 <K3 <K2 <K1 (1)
STEP 5 in FIG. 3 is processing by the allowable upper limit temperature determining means 47. The allowable upper limit temperature determining means 47 evaporates from the target blowing temperature determined by the air-conditioning control means 45 based on the situation where the vehicle detected by the vehicle condition detecting means 41 is placed and the temperature set by the air-conditioning switch 36. The allowable upper limit temperature Eu of the vessel 12 is determined.

  Here, the vehicle state detection means 41 has three elements: the amount of solar radiation detected by the solar radiation sensor 33, the temperature inside the vehicle interior detected by the vehicle interior temperature sensor 31, and the outside air temperature detected by the outside air temperature sensor 32. To detect the situation where the vehicle is placed. And the air-conditioning control means 45 sets target blow temperature higher than preset temperature according to the condition where the vehicle was put, for example, when outside temperature is high.

  In this case, the outside air temperature sensor 32 and the vehicle interior sensor 31 correspond to the supply air temperature detecting means of the present invention. When outside air is supplied to the evaporator 12, the outside air temperature sensor 32 supplies the outside air to the evaporator 12. The air temperature is detected. When air in the vehicle compartment is supplied to the evaporator 12, the temperature of the air supplied to the evaporator 12 is detected by the vehicle compartment sensor 31.

  Then, the allowable upper limit temperature determining means 47 applies the target blow temperature determined by the air conditioning control means 45 to a correlation map between the target blow temperature and the allowable upper limit temperature of the evaporator 12 that is determined in advance by experiments or computer simulation. Then, the allowable upper limit temperature Eu is determined. The correlation map data is stored in a memory (not shown) of the control means 4.

  In subsequent STEP5, the engine stop time determining means 43 determines the room temperature increase allowable time Tu, which is the stop time of the engine 2 in the temperature increase range in which the comfort in the passenger compartment can be maintained, by the following equation (2).

Tu = 1 / Kt · (Eu-Es) (2)
However, Tu: room temperature rise allowable time, Kt: temperature rise coefficient of the evaporator 12 after the engine is stopped, Eu: allowable upper limit temperature of the evaporator 12, Es: detected temperature of the evaporator 12 immediately before the engine is stopped.

  Further, in the next STEP 6, the estimated fog generation time determining means 46 determines the estimated fog generation time Tf, which is the estimated time from when the engine 2 is stopped until the window glass of the vehicle is fogged, using the following equation (3). To do.

Tf = 1 / Kf. (Hd-Hs) (3)
However, Tf: Cloudy occurrence estimation time, Kf: Humidity increase coefficient in the passenger compartment, Hd: Humidity judgment humidity, Hs: Detected humidity in the passenger compartment immediately before engine stop.

  Here, the cloudiness determination humidity estimation means 42 estimates the vicinity of the lower limit value of the humidity at which the cloudiness does not occur in the situation where the vehicle detected by the vehicle condition detection means 41 is placed as the cloudiness determination humidity Hd. The cloudiness determination humidity estimation means 42 obtains the cloudiness determination humidity Hd by applying the situation to the correlation map between the situation where the vehicle detected by the vehicle condition detection means 41 is placed and the cloudiness determination humidity.

  When the cloudiness determination humidity estimation means 42 estimates the cloudiness determination humidity Hd, the vehicle condition detection means 41 detects the vehicle interior temperature detected by the vehicle interior temperature sensor 31, the outside air temperature detected by the outside air temperature sensor 32, and the solar radiation sensor 33. Based on the amount of solar radiation detected by the vehicle, the vehicle speed detected by the vehicle speed sensor 34 immediately before the vehicle stops, the direction of air blown into the vehicle interior by the blower fan 121 set by the wind direction switch 35, the air conditioning conditions set by the air conditioning switch 36, etc. And detects the situation where the vehicle is placed.

  Further, a correlation map between the situation where the vehicle detected by the vehicle situation detection means 41 is placed and the cloudiness determination humidity is determined by experiments, computer simulations, and the like, and the data of the map is stored in a memory (not shown) in advance. ing. Further, the cloudiness determination humidity Hd may be obtained not by using a map but by a correlation equation between the situation where the vehicle is placed and the cloudiness determination humidity Hd.

  Further, the estimated fog generation time determination means 46 determines the humidity increase coefficient Kf in (3) above by (a) stopping the engine 2 with the refrigeration cycle apparatus A and the blower fan 121 operating, and after the engine 2 is stopped. When the blower fan 121 continues to operate, it is set to Ka. (B) The engine 2 is stopped with the refrigeration cycle apparatus A stopped and the blower fan 121 is operating. When the operation is continued, Kb (> Ka) is set. (C) When the blower fan 121 is stopped, the engine 2 is stopped, and when the blower fan 121 continues to stop even after the engine 2 is stopped, Kc ( > Kb).

  When the refrigeration cycle apparatus A and the blower fan 121 are operating when the engine 2 is stopped, the evaporator 12 is cooled. Therefore, even if the refrigeration cycle apparatus A is stopped by stopping the engine 2, the air supplied to the evaporator 12 is dehumidified to some extent if the blower fan 121 is operating.

  Further, when the blower fan 121 is operating while the engine 2 is stopped, the window glass is hardly fogged due to the circulation of air in the passenger compartment. Therefore, by changing the humidity increase coefficient Kf as shown in the following formula (4) under the three conditions (a) to (c), the estimated fog generation time Tf is made difficult to fog on the window glass. Accordingly, it can be determined with higher accuracy.

Ka <Kb <Kc (4)
In the present embodiment, the humidity increase coefficient Kf is set in three stages of Ka, Kb, and Kc according to the above (a) to (c). However, for example, depending on the air volume and direction of the blower fan 121, Further, the temperature increase coefficient Kf may be set in fine steps.

  In subsequent STEP 7, the engine stop time determination means 43 determines whether or not the estimated fog generation time Tf is shorter than the room temperature increase allowable time Tu. When the estimated fog generation time Tf is shorter than the room temperature rise allowable time Tt, the process branches to STEP 10, and the engine stop time determination means 43 sets the estimated fog generation time Tf as the engine stop time Ts. Then, the process proceeds to STEP 9 and the process is terminated.

  On the other hand, if it is determined in STEP 7 that the room temperature increase allowable time Tu is equal to or longer than the cloudy occurrence estimated time Tf, the process proceeds to STEP 8. Then, the engine stop time determining means 43 sets the room temperature rise allowable time Tu as the engine stop time Ts.

  As described above, when the estimated fog generation time Tf is shorter than the room temperature increase allowable time Tu, the fog generation estimation time Tf is used as the engine stop time Ts, thereby avoiding fogging of the window glass while the engine 2 is stopped. can do.

  Next, the engine control means 44 executes the flowchart shown in FIG. 4 to execute engine stop / restart processing.

  The engine control unit 44 determines whether or not a stop condition for the engine 2 is satisfied in STEP 51. Here, as the stop condition of the engine 2, for example, (a) the remaining charge amount of the battery 18 is sufficient, (b) the air conditioner 1 permits the engine 2 to stop, (c) the detected humidity of the humidity sensor 30 It is set to satisfy all three conditions that Hs is lower than the cloudiness determination humidity Hd.

  Then, the engine control means 44 proceeds to STEP 52 to stop the engine 2 when the stop condition of the engine 2 is satisfied in STEP 51, and branches to STEP 58 when the stop condition of the engine 2 is not satisfied, and ends the processing. .

  After stopping the engine 2 in STEP 52, the process proceeds to STEP 53, where the engine control means 44 starts the blower fan 121 (continues the operation when the blower fan 121 is already operating). In STEP 54, the engine control means 44 starts an engine start timer that uses the engine stop time Ts determined in STEP 8 or STEP 10 in FIG. Then, when the engine start timer expires in subsequent STEP 55, the routine proceeds to STEP 56 and the engine 2 is started.

  In subsequent STEP57, the engine control means 44 activates the refrigeration cycle apparatus A via the air conditioning control means 45, proceeds to STEP58, and ends the process. Since the cooling and dehumidification of the passenger compartment are started by the activation of the refrigeration cycle apparatus A, the temperature of the passenger compartment is further increased to prevent the passengers from feeling uncomfortable and the window glass is fogged. This can be prevented.

  In the present embodiment, the estimated fog generation time Tf is determined by STEP 6 to STEP 8 and STEP 10 in FIG. 3, and the shorter of the estimated fog generation time Tf and the room temperature increase allowable time Tu is defined as the engine stop time Ts. However, the effect of the present invention can also be obtained when the room temperature increase allowable time Tu is unconditionally set to the engine stop time Ts without obtaining the cloudy generation estimated time Tf.

  Further, in the present embodiment, as shown in FIG. 2, the temperature increase coefficient Kt of the evaporator 12 is set by switching in six stages K1 to K6, but depending on the temperature of the air supplied to the evaporator 12, etc. The temperature increase coefficient Kt of the evaporator 12 may be set by switching more finely.

  In the above-described embodiment, an example in which the present invention is applied to a hybrid vehicle has been described. However, the present invention is not limited to an idle stop vehicle provided with an automatic idling stop function for automatically stopping and restarting the engine. Can be applied.

The block diagram of the vehicle carrying the vehicle control apparatus of this invention. The flowchart for determining the temperature rise coefficient of an evaporator. The flowchart for determining an engine stop time. The flowchart for restricting the temperature rise in a vehicle interior and preventing fogging of a window glass, and stopping an engine temporarily.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Air conditioning apparatus, 2 ... Engine, 4 ... Control apparatus (vehicle control apparatus), 6 ... Compressor, 9 ... Condenser, 12 ... Evaporator, 30 ... Humidity sensor, 31 ... Inside temperature sensor, 32 ... Outside temperature Sensor, 33 ... Solar radiation sensor, 34 ... Vehicle speed sensor, 35 ... Wind direction switch, 36 ... Air conditioning switch, 41 ... Vehicle condition detection device, 42 ... Cloudiness determination humidity estimation means, 43 ... Engine stop time determination means, 44 ... Engine control means 45 ... Air conditioning control means 46 ... Cloudy generation estimated time determination means 47 ... Allowable upper limit temperature determination means 121 ... Blower fan A ... Refrigeration cycle apparatus G ... Motor / generator H ... Heater core

Claims (5)

An engine; a blower fan for supplying air from outside the vehicle to the vehicle interior or circulating air in the vehicle interior; a refrigerant circulation path; a compressor connected to the refrigerant circulation path and driven by the engine; and the refrigerant circulation path An evaporator provided in an air flow path to the vehicle interior by the blower fan connected to the vehicle, and operating the compressor and the blower fan to cool the vehicle interior A vehicle control device comprising engine control means for stopping the engine when a predetermined stop condition is satisfied and then starting the engine when a predetermined engine stop time has elapsed;
Supply air temperature detection means for detecting the temperature of air supplied to the evaporator by the operation of the blower fan;
Evaporator temperature detecting means for detecting the temperature of the evaporator;
Engine stop time determining means for determining the engine stop time based on the detected temperature of the evaporator temperature detecting means and the detected temperature of the supply air temperature detecting means immediately before stopping the engine,
The engine control means operates the blower fan even when the engine is stopped when the stop condition is satisfied and stops the engine, and starts the compressor by starting the engine when the engine stop time has elapsed. A control apparatus for a vehicle, characterized in that Vehicle situation detection means for detecting the situation where the vehicle is placed;
An allowable upper limit temperature determining means for determining an allowable upper limit temperature of the evaporator in accordance with a target blowing temperature of air into the vehicle interior under the condition detected by the vehicle condition detecting means;
The engine stop time determining means sets the engine stop time to a longer time as the temperature difference between the detected temperature of the evaporator temperature detecting means and the allowable upper limit temperature immediately before stopping the engine is larger. The vehicle control device according to claim 1.   3. The vehicle according to claim 1, wherein the engine stop time determination unit determines the engine stop time to be shorter as the amount of air blown into the vehicle interior by the blower fan is larger. Control device.   The engine stop time determining means is configured such that when air inside the vehicle compartment is supplied to the evaporator by the blower fan while the engine is stopped, air outside the vehicle is supplied to the evaporator by the blower fan. The vehicle control device according to any one of claims 1 to 3, wherein the engine stop time is set to a longer time. Under the conditions detected by the vehicle condition detection means, a fog determination humidity estimation means for estimating a fog determination humidity that is a humidity at which fog does not occur on the window glass of the vehicle;
Humidity detection means for detecting the humidity in the passenger compartment;
The estimated fogging time, which is the estimated time until the windowpane is fogged after the engine is stopped, becomes longer as the humidity difference between the humidity detected by the humidity detecting means and the fogging determination humidity immediately before the engine stops is larger. And a cloudy generation estimated time determining means for determining,
The engine control means stops the engine after the stop condition is satisfied and when the estimated fog occurrence time elapses before the engine stop time elapses, when the estimated fog occurrence time elapses. The vehicle control device according to any one of claims 1 to 4, wherein the compressor is operated while starting.

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