JP2010281229A - Automatic stop and start-up control device of internal combustion engine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve the problem, wherein defogging control by air conditioning system cannot be performed until an engine 10 is restarted up, and driver's visibility cannot be secured, when fog is produced on a window glass 56 during automatic stop or start-up of an engine 10 via an idle stop control. <P>SOLUTION: During automatic stop of an engine 10, the relative humidity close to the inner surface of a window glass 56 is calculated, based on an output value of a humidity sensor 66. Then, if it is determined that the relative humidity is equal to or greater than a predetermined threshold, it is determined that fog is produced on the window glass 56. Then, the engine 10 is restarted, and energization to an electromagnetic clutch 34 is started to perform defogging control. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention includes a compressor that is driven by the rotational force of an output shaft of an internal combustion engine to compress refrigerant, and an evaporator that evaporates refrigerant discharged from the compressor and dehumidifies air. The present invention relates to an automatic stop / start control device for an internal combustion engine that is applied to a vehicle including an air conditioning system and performs an automatic stop process and a restart process of the internal combustion engine.

  Conventionally, in a vehicle equipped with an air conditioning system (air conditioner system), such as temperature control for cooling and heating the interior of the vehicle and control for removing fog (dew condensation on the surface of the vehicle interior side of the window) of the vehicle window What performs air-conditioning control is known. Specifically, the air conditioner system includes an engine-driven compressor, an evaporator that cools and dehumidifies air by evaporating the refrigerant discharged and supplied from the compressor, and a heater that heats the air. ing. Then, by supplying air cooled and dehumidified by the evaporator or air heated by the heater into the vehicle interior, it is possible to perform air conditioning control in the vehicle interior.

  Some of the vehicles are subjected to idle stop control. The idle stop control is to automatically stop the internal combustion engine when a predetermined stop condition is satisfied during the idling operation of the internal combustion engine, and then restart the internal combustion engine when the predetermined restart condition is satisfied. According to this control, it is possible to obtain the fuel consumption reduction effect of the internal combustion engine.

  Here, when the internal combustion engine is automatically stopped by the idle stop control, the compressor constituting the air conditioner system is not driven. For this reason, some of the vehicles described above stop air conditioning control in the passenger compartment while the internal combustion engine is automatically stopped. However, in this vehicle, the air conditioning control is stopped by the automatic stop of the internal combustion engine even though the passenger has instructed to perform the air conditioning control. There is a risk that it will not be possible.

  Therefore, conventionally, as seen in Patent Document 1 below, when it is determined that the air conditioning control in the passenger compartment is being performed, a technique for prohibiting the automatic stop of the internal combustion engine and continuing the air conditioning control is also proposed. Has been. Thereby, it becomes possible to perform air-conditioning control of the vehicle interior according to a passenger | crew's request | requirement.

JP 2001-027139 A

  By the way, under the situation where the humidity in the passenger compartment becomes high, the window may be fogged. This fogging can be removed by the antifogging control. However, when the fogging of the window occurs during the automatic stop of the internal combustion engine, since the air conditioning control is stopped, the fogging of the window cannot be removed, and the driver's view may not be ensured.

  The present invention has been made in order to solve the above-described problems, and an object of the present invention is to promptly cause the air conditioning system to perform anti-fogging control when window fogging occurs during automatic stop of the internal combustion engine. An object of the present invention is to provide an automatic stop / start control device for an internal combustion engine.

  Hereinafter, means for solving the above-described problems and the operation and effects thereof will be described.

  The invention described in claim 1 includes a compressor that is driven by the rotational force of the output shaft of the internal combustion engine and compresses the refrigerant, and an evaporator that evaporates the refrigerant discharged from the compressor and dehumidifies the air. In an automatic stop / start control apparatus for an internal combustion engine, which is applied to a vehicle including an air conditioning system configured as described above and performs an automatic stop process and a restart process of the internal combustion engine, a user instructs removal of fog on the window of the vehicle When the user instructs the removal of defogging via the instruction means and the instruction means, the defogging is performed to control the defogging of the window by supplying the air whose temperature is adjusted by the air conditioning system into the passenger compartment. A humidity information acquisition unit that acquires information about the humidity on the vehicle interior side of the window, and a humidity on the vehicle interior side that is calculated from an output value of the humidity information acquisition unit. A fog determining means for determining whether or not the window has been fogged, and if it is determined that the window is fogged during the automatic stop of the internal combustion engine, the presence or absence of the instruction via the indicating means is determined. Regardless, it is characterized by comprising forcibly executing means for restarting the internal combustion engine and causing the defogging means to perform defogging control.

  When window fogging (condensation on the vehicle interior side surface of the window) occurs, the window is controlled by anti-fogging control in which an instruction from the user via the instruction means is input to supply the temperature-adjusted air into the vehicle interior. It is possible to remove fogging. Here, if the air conditioning control by the air conditioning system is stopped during the automatic stop of the internal combustion engine, the window may be fogged during the automatic stop of the internal combustion engine. In this case, the anti-fogging control cannot be performed until the internal combustion engine is restarted, and the driver's visibility may not be ensured. In this regard, in the above-described invention, it is possible to determine whether or not the window is fogged during the automatic stop of the internal combustion engine based on the fact that the fogging determination unit is provided and the humidity inside the vehicle interior of the window exceeds a predetermined value. it can. When it is determined that the window is fogged, the internal combustion engine is promptly restarted to perform the fog prevention control regardless of the presence or absence of the user's fog prevention control instruction via the instruction means. As a result, when the window is fogged during the automatic stop of the internal combustion engine, the fog can be quickly removed, and the driver's visibility can be secured.

  According to a second aspect of the present invention, in the first aspect of the invention, the forcible execution means can transmit the rotational force of the output shaft of the internal combustion engine to the compressor during the restart process period of the internal combustion engine. The defogging means performs the removal control by supplying the air dehumidified by the evaporator into the passenger compartment.

  In the above invention, since the refrigerant in the refrigeration cycle is circulated by driving the compressor during the restart processing period of the internal combustion engine, air is dehumidified quickly by the evaporator from the time when the restart of the internal combustion engine is started. Can do. Thereby, the dehumidified air can be used for the anti-fogging control, and as a result, the fogging of the window can be quickly removed from the time when it is determined that the fogging of the window occurs.

  The invention according to claim 3 is the invention according to claim 2, wherein the vehicle is provided with an electric motor that is supplied with power from a storage battery and applies initial rotation to an output shaft of the internal combustion engine, and the forcible execution means includes: When it is determined that the power supply voltage of the storage battery is equal to or lower than a predetermined value, consumption of the rotational force of the output shaft of the internal combustion engine by the compressor is limited until the start of the internal combustion engine is completed.

  If the power supply voltage of the storage battery is low, the rotational force of the electric motor may be reduced. In this case, when the compressor is driven during the restart of the internal combustion engine, initial torque is applied to the output shaft of the internal combustion engine due to the rotational force of the electric motor being used for driving the compressor (cranking). The rotational force required to perform the operation of the internal combustion engine may be insufficient. In this regard, in the above invention, when it is determined that the power supply voltage of the storage battery is low, the consumption of the rotational force of the output shaft of the internal combustion engine by the compressor is limited until the restart of the internal combustion engine is completed. Thereby, the rotational force of the electric motor required for performing cranking can be ensured, and by extension, the startability of the internal combustion engine can be prevented from being lowered.

The figure which shows the whole structure of the engine system and air-conditioner system concerning one Embodiment. The flowchart which shows the procedure of the idle stop control process concerning one Embodiment. The time chart which shows the idle stop control process concerning one Embodiment.

  Hereinafter, an embodiment in which an automatic stop / start control apparatus for an internal combustion engine according to the present invention is applied to a vehicle (automobile) equipped with an internal combustion engine (engine) will be described with reference to the drawings.

  FIG. 1 shows the overall configuration of an engine system and an air conditioning system (air conditioner system) according to this embodiment.

  The illustrated engine 10 is a spark ignition internal combustion engine. In each cylinder of the engine 10, a fuel injection valve 12 for injecting and supplying fuel to the combustion chamber of the engine 10, and an ignition plug for generating a discharge spark for combusting an air-fuel mixture of the supplied fuel and intake air 14 are provided. The energy generated by the combustion of the fuel is extracted as the rotational force of the output shaft (crankshaft 16) of the engine 10.

  A starter 18 is connected to the crankshaft 16. The starter 18 starts when power is supplied from the battery 20 when an ignition switch (not shown) is turned on, and applies initial rotation (cranking) to the crankshaft 16 to start the engine 10.

  On the other hand, the air conditioner system includes an air conditioning case 22 that forms an air passage for supplying warm air or cold air into the vehicle interior, and a refrigeration device 24 for cooling and dehumidifying the air flowing through the air passage. .

  The refrigeration apparatus 24 includes a compressor 26 that sucks and discharges refrigerant to circulate the refrigerant in the refrigeration cycle, a condenser 28 that condenses the refrigerant discharged and supplied from the compressor 26, a receiver 30 into which the condensed refrigerant flows, and Is configured to include an evaporator 32 (evaporator) and the like.

  The compressor 26 is a fixed displacement compressor having a constant discharge capacity during driving, and is mechanically connected to the crankshaft 16 via an electromagnetic clutch 34, a belt 36, and a crank pulley 38. Thus, the electromagnetic clutch 34 is brought into the connected state, the rotational force of the crankshaft 16 is transmitted to the compressor 26 and the compressor 26 is driven, while the electromagnetic clutch 34 is brought into the disconnected state, Since the rotational force is not transmitted to the compressor 26, the compressor 26 is not driven. The condenser 28 is a member that exchanges heat between the air blown from the condenser fan 40 that is rotationally driven by a DC motor or the like, and the refrigerant that is discharged and supplied from the compressor 26. The receiver 30 is provided for gas-liquid separation of the refrigerant flowing in from the condenser 28, temporarily storing the separated liquid refrigerant, and supplying only the liquid refrigerant downstream.

  The liquid refrigerant stored in the receiver 30 is rapidly expanded by the temperature type expansion valve 42 into a mist. The atomized refrigerant is supplied to the evaporator 32. The evaporator 32 is provided in the air conditioning case 22, and in the evaporator 32, the refrigerant flows through heat exchange between the air flowing through the air passage of the air conditioning case 22 and the mist-like refrigerant. Thereby, it becomes possible to cool and dehumidify the air flowing through the air passage. Note that the refrigerant evaporated by the evaporator 32 is sucked into the suction port of the compressor 26.

  On the other hand, the air conditioning case 22 is disposed on the front side of the vehicle interior of the vehicle (for example, inside the instrument panel), and in the air conditioning case 22, a blower 44 that generates an air flow in an air passage in the case. In addition, the evaporator 32 and the heater core 46 for heating the air flowing through the air passage are provided.

  Here, the blower 44 is a blower (centrifugal blower) that generates an air flow when a fan is rotationally driven by a DC motor or the like. By generating an air flow with the blower 44, air in the vehicle interior (inside air) is introduced from the inside air suction port 48 formed in the air conditioning case 22, or air outside the vehicle room is introduced from the outside air suction port 50 formed in the case. (Outside air) is introduced. An intake door 52 that is driven by a servo motor or the like is provided inside these suction ports. When the intake door 52 is driven, one of these suction ports is opened, and one of the outside air and the inside air is introduced into the air conditioning case 22.

  The air blown by the blower 44 passes through the evaporator 32 and the heater core 46 and is heat-exchanged so as to reach a desired temperature. Specifically, the evaporator 32 is provided so as to block the entire air passage on the downstream side of the blower 44, and the heater core 46 is provided so as to partially close the air passage on the downstream side of the evaporator 32. Inside the heater core 46, cooling water for the engine 10 supplied from a cooling water pipe (not shown) flows. In the heater core 46, the air flowing through the air passage and the cooling water exchange heat so that the air flowing through the air passage can be heated. An air mix door 54 that is driven by a servo motor or the like is provided between the evaporator 32 and the heater core 46. The air mix door 54 adjusts the ratio of the amount of air passing through the heater core 46 and the amount of air bypassing the heater core 46 according to the stop position. Thereby, the temperature of the air flowing through the air passage can be adjusted.

  The air that has passed through the evaporator 32 and the heater core 46 is supplied from the plurality of air outlets formed in the air conditioning case 22 into the vehicle interior. Specifically, the air conditioning case 22 includes a defroster outlet 58 that blows air toward the inner surface of the front window glass (window glass 56), a face outlet 60 that blows air toward the head and chest of the occupant, and further, A foot outlet 62 that blows air toward the foot is formed. Inside these air outlets, two air outlet switching doors 64a and 64b driven by a servo motor or the like are provided. By driving these air outlet switching doors 64a and 64b, the air outlet mode is switched to any one of a face mode (FACE mode), a defroster mode (DEF mode), a foot mode (FOOT mode), and the like. Specifically, the FACE mode is a mode in which the entire amount of air introduced into the air passage is blown out from the face outlet 60. The DEF mode is a mode in which the entire amount of the introduced air is blown out from the defroster outlet 58. Further, the FOOT mode is a mode in which most of the introduced air (about 80%) is blown out from the foot outlet 62 and the remaining air is blown out from the defroster outlet 58.

  A humidity sensor 66 is provided near the vehicle interior side surface (inner surface) of the window glass 56 (for example, near the window glass of the dashboard). The humidity sensor 66 outputs a voltage signal proportional to the relative humidity.

  An electronic control device (hereinafter referred to as an air conditioner ECU 68) for operating an air conditioner system is mainly configured by a microcomputer including a known CPU, ROM, RAM, and the like. The air conditioner ECU 68 includes an A / C switch 70 that serves as a drive command for the compressor 26 (energization command to the electromagnetic clutch 34) for cooling and dehumidifying the passenger compartment, and a switch that is operated by the occupant to switch the outlet mode. (Blow-out switch 71), output signals from the humidity sensor 66 and the like are input. The air conditioner ECU 68 operates various devices such as the condenser fan 40, the blower 44, the electromagnetic clutch 34, and the outlet switching doors 64a and 64b by executing various control programs stored in the ROM in response to these inputs. . Then, by operating these various devices, air conditioning control of the vehicle interior such as drive control of the compressor 26 and temperature control of the vehicle interior is performed. In particular, the air conditioner ECU 68 performs control (anti-fogging control) to remove fogging of the window glass 56 (condensation on the vehicle interior side surface of the window glass 56) by blowing warm air from the defroster outlet 58 as air conditioning control in the vehicle interior. Do. The anti-fogging control is performed when this control instruction is given from the occupant via the air outlet changeover switch 71. Specifically, for example, it is performed when the air outlet changeover switch 71 is operated to switch the air outlet mode to the DEF mode.

  On the other hand, an electronic control device (hereinafter referred to as an engine ECU 72) whose operation target is an engine system is mainly composed of a microcomputer composed of a well-known CPU, ROM, RAM and the like. The engine ECU 72 detects a brake sensor 74 that detects the amount of depression of the brake pedal, a vehicle speed sensor 76 that detects the traveling speed of the vehicle, and a shift position (P, N, D range, etc.) of the transmission (automatic transmission). The output signal of the shift position sensor 78 that detects the voltage of the battery 20 and the battery voltage sensor 80 that detects the voltage of the battery 20 are input. In addition, the engine ECU 72 and the air conditioner ECU 68 exchange information by performing bidirectional communication. Specifically, the engine ECU 72 receives signals from the air conditioner ECU 68 such as the A / C switch 70 and the humidity sensor 66. On the other hand, a signal for permitting energization of the electromagnetic clutch 34 output from the engine ECU 72 is input to the air conditioner ECU 68.

  The engine ECU 72 executes various control programs stored in the ROM in response to the above input, thereby controlling the fuel injection by the fuel injection valve 12, the ignition control by the spark plug 14, and the engine 10 by the starter 18. Start control etc. In particular, the engine ECU 72 performs idle stop control of the engine 10. In the idle stop control, the engine 10 is automatically stopped when a predetermined stop condition is satisfied during operation of the engine 10, and then the engine 10 is restarted when a predetermined restart condition is satisfied. Thereby, the fuel consumption reduction effect of the engine 10 can be obtained. Here, the stop condition and the restart condition are set so that the driver's intention to stop and the intention to start the vehicle can be grasped.

  Incidentally, during the automatic stop of the engine 10, the air conditioning control by the air conditioner ECU 68 is stopped. This is based on the fact that the compressor 26 is not driven and the voltage drop of the battery 20 due to power consumption for driving various devices constituting the air conditioner system is avoided. However, when the humidity near the inner surface of the window glass 56 rises during the automatic stop of the engine 10 and the window glass 56 is fogged, the anti-fogging control is performed until the air conditioning control is started after the engine 10 is restarted. The driver's view cannot be secured. In particular, if the window is fogged during the automatic stop of the engine 10, even if the occupant instructs the fog prevention control using the A / C switch 70 or the blow-out switch 71, until the fog prevention control is actually started. The time lag increases. For this reason, when starting the vehicle, there is a concern that a situation in which it is still difficult to secure the driver's field of vision has not been solved.

  Therefore, in the present embodiment, it is determined whether or not the window glass 56 is fogged based on the output value of the humidity sensor 66 during the automatic stop of the engine 10. If it is determined that the window glass 56 is fogged, the engine 10 is restarted and the window glass is controlled by anti-fogging control even if the restart condition based on grasping the intention of starting the vehicle is not satisfied. Remove 56 haze.

  FIG. 2 shows a procedure of idle stop control processing according to the present embodiment. This process is repeatedly executed by the engine ECU 72 at a predetermined cycle, for example.

  In this series of processing, first, in step S10, it is determined whether or not the automatic stop flag F is set to “1”. This process is for determining whether or not the engine 10 is automatically stopped. Here, the automatic stop flag F indicates that the engine 10 is not automatically stopped by “0”, and indicates that it is automatically stopped by “1”.

  When it is determined in step S10 that the automatic stop flag F is not set to “1”, the process proceeds to step S12, and it is determined whether or not a stop condition for the engine 10 is satisfied. Here, the stop condition is a logical product condition of a condition that the brake operation is performed and a condition that the traveling speed of the vehicle becomes 0 (or substantially 0). Note that whether or not the brake operation is being performed may be determined based on the output value of the brake sensor 74. Whether the traveling speed of the vehicle becomes 0 (or substantially 0) may be determined based on the output value of the vehicle speed sensor 76.

  If it is determined in step S12 that the engine 10 stop condition is satisfied, the process proceeds to step S14, and the engine 10 is automatically stopped. Here, the automatic stop process is a process for stopping the engine 10 by stopping the fuel injection from the fuel injection valve 12. Then, after confirming that the engine 10 has stopped, the automatic stop flag F is set to “1”.

  On the other hand, if it is determined in step S10 that the automatic stop flag F is set to “1”, the process proceeds to step S16, and the engine 10 is restarted in response to the determination that the vehicle is ready to start. It is determined whether the condition is satisfied. Here, the restart condition is a logical product condition of a condition that the brake operation is not performed and a condition that the shift position is in the driving state. Whether or not the shift position is in the drive state may be determined based on the output value of the shift position sensor 78.

  If it is determined in step S16 that the restart condition of the engine 10 is satisfied, the process proceeds to step S18, and the engine 10 is automatically started. Here, the automatic start process is a process of performing cranking by starting the starter 18 and restarting the engine 10 that is automatically stopped by operating the fuel injection valve 12 and the spark plug 14. Then, after confirming that the engine 10 has started, the automatic stop flag F is set to “0”.

  On the other hand, if it is determined in step S16 that the restart condition of the engine 10 is not satisfied, the process proceeds to step S20, where the relative humidity Hwin near the inner surface of the window glass 56 is a predetermined threshold TMP (for example, 80% RH). ) Determine whether it is above. This processing is for determining whether or not the window glass 56 is fogged in view of the increase in relative humidity near the inner surface of the window glass 56 causing the window glass 56 to be clouded. The predetermined threshold value TMP is desirably set according to the degree of suppression of fogging of the window glass 56 and the request for the fuel consumption reduction effect of the engine 10 by idle stop control. That is, when priority is given to suppressing the occurrence of fogging of the window glass 56, the threshold value TMP may be set to a low value. Further, for example, when priority is given to the fuel consumption reduction effect of the engine 10 by the idle stop control, the threshold value TMP may be set to a high value. The relative humidity Hwin near the inner surface of the window glass 56 may be calculated based on the output value of the humidity sensor 66 acquired from the air conditioner ECU 68.

  If it is determined in step S20 that the window glass 56 is fogged, the process proceeds to step S22 to determine whether or not the voltage Vb of the battery 20 is equal to or higher than a predetermined threshold value BATT. This process is for grasping whether or not the driving force required for both the compressor 26 and the cranking can be secured by the rotational force of the starter 18. The voltage Vb of the battery 20 may be calculated based on the output value of the battery voltage sensor 80.

  If it is determined in step S22 that the voltage Vb of the battery 20 is equal to or higher than the predetermined threshold value BATT, it is determined that the driving force required for both of the above can be secured, and the process proceeds to step S24. In step S24, an automatic start process of the engine 10 is performed and an anti-fogging control is commanded to the air conditioner ECU 68. As a result, the air conditioner ECU 68 starts energization of the electromagnetic clutch 34 by using the anti-fogging control command as a trigger, and operates the air outlet switching doors 64a and 64b to switch the air outlet mode so that the anti-fogging control is performed in the DEF mode. I do. As a result, the air can be dehumidified by the evaporator 32 immediately after the restart of the engine 10 is started. Then, by blowing out the dehumidified air from the defroster outlet 58, it is possible to quickly remove the fogging of the window glass 56 from the time when it is determined that the fogging of the window glass 56 occurs.

  On the other hand, when it is determined in step S22 that the voltage Vb of the battery 20 is smaller than the predetermined threshold value BATT, the process proceeds to step S26, and an energization command to the electromagnetic clutch 34 is issued (the A / C switch 70 is turned on). It is determined whether it is ON). This process is for determining whether or not there is a drive command to the compressor 26. Note that whether or not a command to energize the electromagnetic clutch 34 has been made may be determined based on the output value of the A / C switch 70 acquired from the air conditioner ECU 68.

  If it is determined in step S26 that an energization command to the electromagnetic clutch 34 has been made, the process proceeds to step S28, and the output of the energization command to the electromagnetic clutch 34 is stopped. This process is for avoiding a decrease in startability of the engine 10. That is, when the voltage Vb of the battery 20 is low, the rotational force of the starter 18 may be reduced. In this case, when the compressor 26 is driven during the restart of the engine 10, the rotational force of the starter 18 is also used for driving the compressor 26, and the rotational force of the starter 18 required for cranking is insufficient. There is a possibility that the startability of 10 may be lowered. For this reason, until the restart of the engine 10 is completed, even if there is a drive command for the compressor 26, the compressor 26 is not driven and the consumption of the rotational force of the crankshaft 16 by the compressor 26 is limited. As a result, it is possible to avoid a decrease in startability of the engine 10 by securing the rotational force of the starter 18 required for cranking.

  If it is determined in step S26 that a command to energize the electromagnetic clutch 34 has not been made (the A / C switch 70 is OFF), or if the process of step S28 is completed, the step S24 is performed. Then, the engine 10 is automatically started and the anti-fogging control is commanded to the air conditioner ECU 68. Here, the air conditioner ECU 68 starts energization of the electromagnetic clutch 34 by using a signal output from the engine ECU 72 indicating that the restart of the engine 10 has been confirmed as a trigger, and performs anti-fogging control in the DEF mode. Thereby, it is possible to remove the fogging of the window glass 56 as quickly as possible from the time when it is determined that the fogging of the window glass 56 occurs, while avoiding a decrease in the startability of the engine 10.

  When a negative determination is made in steps S12 and S20 or when the processes in steps S14, S18, and S24 are completed, the series of processes is temporarily terminated.

  FIG. 3 shows an example of the idle stop control process in the present embodiment. Specifically, FIG. 3A shows the transition of the driving state of the engine 10, FIG. 3B shows the transition of the engine automatic stop request flag, and FIG. 3C shows the window glass fogging flag. FIG. 3D shows the transition of the battery voltage determination flag, and FIG. 3E shows the transition of the energization command to the electromagnetic clutch 34. The battery voltage determination flag indicates that the voltage Vb of the battery 20 is equal to or higher than the predetermined threshold value BATT when “ON”, and indicates that it is smaller than the predetermined threshold value BATT when “OFF”.

  As shown in the figure, the engine automatic stop request flag is turned ON when the stop condition of the engine 10 is satisfied at time t1. Thereby, the engine 10 is automatically stopped and the air conditioning control is stopped. Thereafter, at time t2 when the engine 10 is automatically stopped, it is determined that the window glass 56 is fogged (affirmative determination is made in step S20 in FIG. 3), and the window glass fogging determination flag is turned on. The As a result, the engine automatic stop request flag is turned off, whereby the engine 10 is restarted and energization of the electromagnetic clutch 34 is started to perform the anti-fogging control.

  FIG. 3 (f) and FIG. 3 (g) show the idle stop control process according to the prior art. As shown in the figure, at time t1, the engine 10 is automatically stopped and the air conditioning control is stopped. Thereafter, the fogging of the window glass 56 occurs at time t2, but since the engine 10 is not restarted until time t3, the anti-fogging control cannot be performed quickly.

  As described above, in the present embodiment, when the window glass 56 is fogged while the engine 10 is automatically stopped, the engine 10 is restarted even if the occupant is not instructed to perform the anti-fogging control via the air outlet changeover switch 71. The fogging of the window glass 56 can be quickly removed by starting and performing antifogging control.

  According to the embodiment described in detail above, the following effects can be obtained.

  (1) While the engine 10 is automatically stopped, when it is determined that the relative humidity Hwin near the inner surface of the window glass 56 is equal to or higher than the predetermined threshold value TMP, the engine 10 is restarted and energization of the electromagnetic clutch 34 is started. Then, antifogging control was performed. Thus, even if the occupant is not instructed to perform the antifogging control via the air outlet changeover switch 71, the fogging of the window glass 56 that occurs during the automatic stop of the engine 10 can be quickly removed. Visibility can be secured. Further, since the humidity sensor 66 is installed in the vicinity of the inner surface of the window glass 56, the relative humidity Hwin in the vicinity of the inner surface of the window glass 56 can be detected with high accuracy, and as a result, whether or not the window glass 56 is fogged can be detected with high accuracy. You can also grasp.

  (2) When it is determined that the voltage Vb of the battery 20 is smaller than the predetermined threshold value BATT and it is determined that the energization command to the electromagnetic clutch 34 has been issued, the electromagnetic force is reduced until the restart of the engine 10 is completed. Energization of the clutch 34 was stopped. As a result, the rotational force of the starter 18 required for cranking can be ensured, and as a result, the startability of the engine 10 can be prevented from being lowered.

(Other embodiments)
The above embodiment may be modified as follows.

  In the above embodiment, the engine 10 is restarted and energization of the electromagnetic clutch 34 is started to perform the anti-fogging control, but this is not restrictive. For example, the anti-fogging control may be performed without energizing the electromagnetic clutch 34. Even in this case, it is possible to increase the inner surface temperature of the window glass 56 by blowing out the warm air heated by the heater core 46, and to reduce the relative humidity in the vicinity of the inner surface of the window glass 56. Haze can be removed. Further, the power consumption of the battery 20 by the blower 44 or the like can be compensated by driving the engine 10. This is because power generation control by an alternator (not shown) can be performed according to the charge amount (SOC) of the battery 20 while the engine 10 is being driven. On the other hand, when the blower 44 or the like is driven while the engine 10 is stopped, the charge amount (SOC) of the battery 20 is reduced, and there is a concern that the restartability of the engine 10 is lowered.

  In the above embodiment, when it is determined that the relative humidity Hwin in the vicinity of the inner surface of the window glass 56 is equal to or higher than the predetermined threshold value TMP, it is determined that the window glass 56 is fogged, but this is not a limitation. For example, it has an absolute humidity detecting means for detecting the absolute humidity near the inner surface of the window glass 56 and a temperature detecting means for detecting the inner surface temperature of the window glass 56, and the absolute humidity is associated with the inner surface temperature based on the output value of these means. If it is determined that the predetermined threshold value is exceeded, it may be determined that the window glass 56 is fogged. Here, the predetermined threshold may be set higher as the inner surface temperature of the window glass 56 becomes higher. This is based on the fact that when the inner surface temperature of the window glass 56 increases, the absolute humidity at which the window glass 56 begins to fog up increases.

  In the above embodiment, the compressor 26 is a fixed capacity compressor, but is not limited thereto. For example, a variable displacement compressor in which the refrigerant discharge capacity can be variably set by an energization operation may be used. In this case, the electromagnetic clutch 34 may not be provided (clutchless). In this case, the rotational force consumed by the compressor 26 depends on the discharge capacity. Therefore, for example, if it is determined in step S26 of FIG. 2 that the A / C switch 70 is in the ON state, the discharge capacity may be limited until the restart of the engine 10 is completed in step S28. .

  The instruction means for instructing the occupant to perform the anti-fogging control is not limited to the air outlet changeover switch 71. For example, instead of this switch, if the dial is provided to switch the outlet mode, this dial may be used as the instruction means.

  Control for removing fogging of the window glass 56 by supplying air whose temperature is adjusted by the air conditioning system into the vehicle interior (antifogging control) is not limited to that performed in the DEF mode. For example, by performing anti-fogging control in a mode other than the DEF mode, the humidity near the inner surface of the window glass 56 may be reduced, and the fogging of the window glass 56 may be removed.

  The means for acquiring information on the relative humidity on the vehicle interior side of the vehicle window is not limited to the humidity sensor 66 that detects the relative humidity Hwin in the vicinity of the inner surface of the window glass 56. For example, a means for estimating the relative humidity Hwin may be used. Specifically, for example, it is conceivable to have means for detecting the dry bulb temperature and the wet bulb temperature near the inner surface of the window glass 56 and to estimate the relative humidity Hwin based on the output values of these means.

  -The internal combustion engine is not limited to a spark ignition type internal combustion engine such as a gasoline engine. For example, it may be a compression ignition type internal combustion engine such as a diesel engine.

  The vehicle is not limited to a vehicle that uses only an internal combustion engine as a travel power supply source. For example, even if the vehicle (hybrid vehicle) further includes a rotating machine as a travel power supply source, the application of the present invention is effective if the air conditioning control in the passenger compartment is stopped during the automatic stop of the internal combustion engine. In this case, the rotating machine may be used as a starter (electric motor) that applies initial rotation to the output shaft of the internal combustion engine.

  DESCRIPTION OF SYMBOLS 10 ... Engine, 16 ... Crankshaft, 18 ... Starter, 20 ... Battery, 22 ... Air conditioning case, 24 ... Refrigerating device, 26 ... Compressor, 32 ... Evaporator, 34 ... Electromagnetic clutch, 56 ... Window glass, 66 ... Humidity sensor, 68 ... Air conditioner ECU, 70 ... A / C switch, 71 ... Air outlet changeover switch, 72 ... Engine ECU (one embodiment of an automatic stop / start control device for an internal combustion engine), 80 ... Battery voltage sensor.

Claims (3)

An air conditioning system comprising a compressor that is driven by the rotational force of the output shaft of an internal combustion engine and compresses the refrigerant, and an evaporator that evaporates the refrigerant discharged from the compressor and dehumidifies the air. In an automatic stop / start control device for an internal combustion engine that is applied to a vehicle comprising:
Instruction means for a user to instruct defrosting of the vehicle window;
When the mist removal is instructed by the user via the instruction means, the defogging means for performing control to remove the fogging of the window by supplying the air whose temperature is adjusted by the air conditioning system into the vehicle interior;
Humidity information acquisition means for acquiring information about the humidity inside the vehicle interior of the window;
A fog determination unit that determines whether or not the window has been fogged based on the fact that the humidity on the vehicle interior side calculated from the output value of the humidity information acquisition unit exceeds a predetermined value;
When it is determined that the window is fogged during the automatic stop of the internal combustion engine, the internal combustion engine is restarted and the fog removal means is removed by the fog removal means regardless of the presence or absence of the instruction via the indication means. An automatic stop / start control device for an internal combustion engine, comprising: a forced execution means for performing control. The forced execution means is capable of transmitting the rotational force of the output shaft of the internal combustion engine to the compressor during the restart processing period of the internal combustion engine,
2. The automatic stop / start control device for an internal combustion engine according to claim 1, wherein the defogging means performs the removal control by supplying the air dehumidified by the evaporator into the passenger compartment. The vehicle includes an electric motor that is powered by a storage battery and applies initial rotation to an output shaft of the internal combustion engine,
The forced execution means limits the consumption of the rotational force of the output shaft of the internal combustion engine by the compressor until the start of the internal combustion engine when it is determined that the power supply voltage of the storage battery is equal to or lower than a predetermined value. An automatic stop / start control device for an internal combustion engine according to claim 2.

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