Vehicle

Abstract

To inhibit freezing in a throttle part from occurring between trips of a vehicle or inhibit the extent from progressing when freezing is occurring as much as possible.SOLUTION: A vehicle includes an engine provided with a throttle part having a throttle body provided in an intake passage and a throttle valve rotatably supported by the throttle body, and a control device for controlling the engine. The control device executes aperture increasing or decreasing control for increasing or decreasing an aperture of the throttle valve when ending a trip or every prescribed time thereafter if a throttle part freezing condition is established when ending the trip.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present invention relates to a vehicle, and more particularly to a vehicle including an engine having a throttle valve provided in an intake passage.

Background Art

[0002] Conventionally, when the engine is stopped, it is determined whether or not the freezing condition of the throttle valve is satisfied based on the intake air temperature and the coolant temperature of the engine. When the freezing condition is not satisfied, the throttle valve is controlled to be fully closed to stop the engine. When the freezing condition is satisfied, a vehicle has been proposed in which the engine is stopped while maintaining the throttle valve in an open state (see, for example, Patent Document 1). In this vehicle, such control suppresses the throttle valve from freezing in the fully closed state when the engine is stopped.

[0003] Also, when the engine is stopped, the throttle valve is opened by a first reference opening degree, and when the engine is started, the throttle valve is opened from the first reference opening degree to a second reference opening degree on the opening side and then fully closed (see, for example, Patent Document 2). In this vehicle, such control removes the ice around the throttle valve when the engine is started.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0005] In the above Patent Documents 1 and 2, between trips of the vehicle, there is a throttle section having a throttle body and a throttle valve rotatably supported by the throttle body. In particular, freezing may occur between the throttle body and the throttle valve, or when freezing has occurred, the degree of freezing may progress relatively. When the freezing between the throttle body and the throttle valve progresses relatively, it may become difficult to decrease the opening degree of the throttle valve.

[0006] The main object of the vehicle of the present invention is to further suppress the occurrence of freezing in the throttle section and the progression of the degree of freezing when freezing has occurred between trips of the vehicle.

Means for Solving the Problem

[0007] The vehicle of the present invention has adopted the following means in order to achieve the above main object.

[0008] The vehicle of the present invention includes an engine having a throttle section including a throttle body provided in an intake passage and a throttle valve rotatably supported by the throttle body, a control device for controlling the engine, and is a vehicle comprising: when the freezing condition of the throttle section is satisfied when ending a trip, the control device executes an opening degree increase / decrease control for increasing and decreasing the opening degree of the throttle valve at the time of ending the trip and at predetermined times thereafter. This is the gist.

[0009] In the vehicle of the present invention, when the freezing condition of the throttle section is satisfied when ending a trip, opening degree increase / decrease control for increasing or decreasing the opening degree of the throttle valve is executed at the time of ending the trip and at each predetermined time thereafter. Here, "when ending the trip" means when the ignition switch (start switch) of the vehicle is turned off and the system stops (travel is prohibited). Also, when the engine is running "when ending the trip", the operation is stopped, and when the engine operation is stopped, it is maintained. The "freezing condition of the throttle section" is a condition where freezing has occurred (ice is present) in the throttle section (for example, between the throttle valve and the throttle body) or it is estimated that freezing may occur thereafter, or a condition where freezing has occurred or may occur thereafter in the throttle section and it is estimated that the freezing in the throttle section can be released or water can be removed by executing the opening degree increase / decrease control. By executing the opening degree increase / decrease control at the time of ending the trip and at each predetermined time thereafter, compared to performing the opening degree increase / decrease control only when ending the trip or only when starting the engine during the trip, between trips of the vehicle, the release of freezing in the throttle section and the removal of water can be performed more sufficiently. That is, between trips of the vehicle, it is possible to more effectively suppress the occurrence of freezing in the throttle section or the progression of the degree of freezing if it has already occurred. Note that by more sufficiently performing the release of freezing in the throttle section and the removal of water between trips of the vehicle, the necessity of executing the opening degree increase / decrease control when starting the engine in the next trip is reduced. Although executing the opening degree increase / decrease control when starting the engine may cause the amount of air inhaled into the combustion chamber to fluctuate and may affect the startability of the engine, by reducing the necessity of executing the opening degree increase / decrease control when starting the engine, such inconveniences can be suppressed.

[0010] In the vehicle of the present invention, after the end of the trip, each time the predetermined time has elapsed and before executing the opening degree increase / decrease control, the control device executes determination control for decreasing the opening degree of the throttle valve. Based on at least one of the deviation amount between the opening degree of the throttle valve and the target opening degree, the drive current of the throttle motor that adjusts the opening degree of the throttle valve, and the opening degree change rate which is the amount of change in the opening degree of the throttle valve per unit time during the determination control, it is determined whether or not the throttle section is frozen. When it is determined that the throttle section is frozen, the first opening degree increase / decrease control is executed as the opening degree increase / decrease control. When it is determined that the throttle section is not frozen, the second opening degree increase / decrease control different from the first opening degree increase / decrease control may be executed as the opening degree increase / decrease control. Here, the "first opening degree increase / decrease control" is control for releasing the freeze of the throttle section. The "second opening degree increase / decrease control" is control for removing water from the throttle section (around the throttle valve). By such control, the first opening degree increase / decrease control or the second opening degree increase / decrease control can be executed according to whether or not the throttle section is frozen.

[0011] In the vehicle of the present invention in an aspect of executing the first opening degree increase / decrease control or the second opening degree increase / decrease control, when at least one of the following conditions is satisfied: the first condition that a state where the deviation amount is equal to or greater than a predetermined deviation amount continues for a first predetermined time or more; the second condition that a state where the absolute value of the drive current is equal to or greater than a first predetermined current and the absolute value of the opening degree change rate is equal to or less than a predetermined change rate continues for a second predetermined time or more; the third condition that a state where the absolute value of the drive current is equal to or greater than a second predetermined current greater than the first predetermined current continues for a third predetermined time or more, it is determined that the throttle section is frozen. When none of the first condition, the second condition, and the third condition is satisfied, it may be determined that the throttle section is not frozen. In this way, it is possible to more appropriately determine whether or not the throttle section is frozen.

[0012] In the vehicle of the present invention in the mode of executing the first opening degree increase / decrease control or the second opening degree increase / decrease control, in the first opening degree increase / decrease control, the control device executes an increase / decrease set of increasing and then decreasing the opening degree of the throttle valve until it is determined that the freezing of the throttle section is released, and in the second opening degree increase / decrease control, the increase / decrease set may be executed a predetermined number of times. By doing so, in the former case, the freezing of the throttle section can be released. Also, in the latter case, the water in the throttle section can be removed.

[0013] In the vehicle of the present invention in the mode of executing the increase / decrease set in the first opening degree increase / decrease control until it is determined that the freezing of the throttle section is released, the control device determines that the freezing of the throttle section is released when all of the following first condition, second condition, and third condition are not satisfied: the first condition that a state where the deviation amount is equal to or greater than a predetermined deviation amount continues for a first predetermined time or more; the second condition that a state where the absolute value of the drive current is equal to or greater than a first predetermined current and the absolute value of the opening degree change rate is equal to or less than a predetermined change rate continues for a second predetermined time or more; and the third condition that a state where the absolute value of the drive current is equal to or greater than a second predetermined current greater than the first predetermined current continues for a third predetermined time or more. By doing so, it is possible to more appropriately determine the release of the freezing of the throttle section.

[0014] In the vehicle of the present invention in the mode of executing the increase / decrease set in the first opening degree increase / decrease control until it is determined that the freezing of the throttle section is released, the throttle valve operates using power from the battery. In the first opening degree increase / decrease control, when it is determined that the freezing of the throttle section is released, if the number of times of the increase / decrease set is less than a first predetermined number of times, the first opening degree increase / decrease control is terminated when the number of times of the increase / decrease set reaches the first predetermined number of times. Even if it is not determined that the freezing of the throttle section is released, the first opening degree increase / decrease control may be terminated when the number of times of the increase / decrease set reaches a second predetermined number of times greater than the first predetermined number of times. By doing so, in the former case, it is possible to more sufficiently separate the ice from around the throttle valve. Also, in the latter case, it is possible to suppress an excessive increase in the power consumption of the battery.

[0015] In the vehicle of the present invention in a mode of executing the first opening degree increase / decrease control or the second opening degree increase / decrease control, when the control device is performing one of the increase and decrease of the opening degree of the throttle valve in the first opening degree increase / decrease control, if it is determined that the throttle valve has bitten into a foreign object, it may resume the one after performing the other different from the one of the increase and decrease of the opening degree of the throttle valve. By doing so, when the throttle valve bites into a foreign object, the biting can be released.

[0016] In this case, when at least one of a fourth condition that a state where the absolute value of the drive current is equal to or greater than a third predetermined current and the absolute value of the opening degree change rate is equal to or less than a second predetermined change rate continues for a fourth predetermined time or more, and a fifth condition that a state where the absolute value of the drive current is equal to or greater than a fourth predetermined current greater than the third predetermined current continues for a fifth predetermined time or more is satisfied, the control device may determine that the throttle valve has bitten into a foreign object. By doing so, it is possible to more appropriately determine whether the throttle valve has bitten into a foreign object.

[0017] In the vehicle of the present invention, in the opening degree increase / decrease control, the control device may increase or decrease the opening degree of the throttle valve more gently in the start section and the end section of the increase or decrease of the opening degree of the throttle valve than in the intermediate section between the start section and the end section. By doing so, it is possible to suppress the rattling sound in the gear mechanism that connects the throttle valve and the throttle motor.

[0018] In the vehicle of the present invention, the freezing condition may be a condition that when ending the trip, the coolant water temperature of the engine is within a water temperature range based on the outside air temperature. In this case, the water temperature range may be set to be higher as the outside air temperature is lower. By doing so, it is possible to more appropriately determine whether the freezing condition is satisfied.

Brief Description of the Drawings

[0019]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Mode for Carrying Out the Invention

[0020] Next, modes for carrying out the present invention will be described using examples.

Example

[0021] FIG. 1 is a configuration diagram showing an outline of the configuration of the motor vehicle 10 as an embodiment of the present invention. As shown in the figure, the motor vehicle 10 of the embodiment includes an engine 12, a starter (not shown), a generator (alternator) 50, a battery 52, a transmission 54, and an electronic control unit 70.

[0022] The engine 12 is configured as an internal combustion engine with multiple cylinders (e.g., 4 cylinders or 6 cylinders, etc.) that outputs power through four strokes of intake, compression, expansion (explosive combustion), and exhaust using fuel such as gasoline or diesel oil. This engine 12 has an in-cylinder injection valve 26 that injects fuel into the cylinder for each cylinder, and a spark plug 30. The engine 12 inhales the air cleaned by the air cleaner 22 into the intake passage 23, passes it through the throttle section 24 provided in the intake passage 23, specifically, the throttle valve 24v rotatably supported by the throttle body 24b provided in the intake passage 23, and further inhales it into the combustion chamber 29 through the intake valve 28. Also, fuel is injected from the in-cylinder injection valve 26 during the intake stroke and the compression stroke, and is explosively combusted by the electric spark from the spark plug 30. Then, the reciprocating motion of the piston 32 pushed down by the energy of the explosive combustion is converted into the rotational motion of the crankshaft 14. The exhaust discharged from the combustion chamber 29 to the exhaust pipe 34 through the exhaust valve 33 is discharged to the outside air through the purification device 35. The purification device 35 has a purification catalyst (three-way catalyst) 35a that purifies harmful components such as carbon monoxide (CO), hydrocarbons (HC), and nitrogen oxides (NOx). Note that power is supplied to the throttle motor 24m that adjusts the opening degree of the throttle valve 24v, the in-cylinder injection valve 26, the spark plug 30, etc. from the power line 51 to which the battery 52 is connected. Also, the throttle valve 24v and the throttle motor 24m are connected via a gear mechanism (not shown).

[0023] The starter is connected to the crankshaft 14 of the engine 12 and is used to crank the engine 12. The generator 50 is connected to the crankshaft 14, generates electricity using the power from the engine 12, and supplies the power to the power line 51 to which the battery 52 is connected. The transmission 54 is connected to the crankshaft 14 of the engine 12 and the drive shaft DS connected to the drive wheels DW via a differential gear DF, and transmits the power from the crankshaft 14 after shifting it to the drive shaft DS.

[0024] The electronic control unit 70 includes a microcomputer having a CPU 71, a ROM 72, a RAM 73, a flash memory 74, and input / output ports. Signals from various sensors are input to the electronic control unit 70 via the input ports. Examples of the signals input to the electronic control unit 70 include the crank angle θcr from the crank position sensor 14a that detects the rotational position of the crankshaft 14 of the engine 12, and the coolant temperature Tw from the water temperature sensor 15 that detects the temperature of the coolant of the engine 12. Also included are the cam angles θci and θco from the cam position sensor 16 that detects the rotational position of the intake camshaft that opens and closes the intake valve 28 and the rotational position of the exhaust camshaft that opens and closes the exhaust valve 33. Further examples include the throttle valve opening TH of the throttle valve 24v from the throttle position sensor 24o that detects the position (opening) of the throttle valve 24v, the drive current Im of the throttle motor 24m from the current sensor 24i attached near the throttle motor 24m on the power line 51, the intake air quantity Qa from the air flow meter 23a attached upstream of the throttle valve 24v in the intake passage 23, and the intake air temperature Ta from the temperature sensor 23t attached upstream of the throttle valve 24v in the intake passage 23. Also included are the front air-fuel ratio AF1 from the front air-fuel ratio sensor 37 attached upstream of the purification device 35 in the exhaust pipe 34 and the rear air-fuel ratio AF2 from the rear air-fuel ratio sensor 38 attached downstream of the purification device 35 in the exhaust pipe 34. Further examples include the rotational speed of the input shaft of the transmission 54 from the rotational speed sensor attached to the input shaft of the transmission 54 and the rotational speed of the output shaft of the transmission 54 from the rotational speed sensor attached to the output shaft of the transmission 54. Also included are the ignition signal IG from the ignition switch 80 and the shift position SP from the shift position sensor that detects the operating position of the shift lever. Further examples include the accelerator opening Acc from the accelerator pedal position sensor that detects the depression amount of the accelerator pedal, the brake pedal position BP from the brake pedal position sensor that detects the depression amount of the brake pedal, and the vehicle speed V from the vehicle speed sensor. Also included is the outside air temperature To from the outside air temperature sensor 82.

[0025] From the electronic control unit 70, various control signals are output via the output ports. Examples of the signals output from the electronic control unit 70 include a control signal to the throttle motor 24m that adjusts the opening degree of the throttle valve 24v of the engine 12, a control signal to the in-cylinder injection valve 26, and a control signal to the spark plug 30. Further, a control signal to a starter (not shown), a control signal to the generator 50, and a control signal to the transmission 54 can also be mentioned.

[0026] The electronic control unit 70 calculates the engine speed Ne of the engine 12 based on the crank angle θcr from the crank position sensor 14a. Further, the electronic control unit 70 calculates the load factor KL of the engine 12 (the ratio of the volume of air actually inhaled in one cycle to the stroke volume per cycle of the engine 12) based on the intake air amount Qa from the air flow meter 23a and the engine speed Ne of the engine 12. Furthermore, the electronic control unit 70 estimates the temperature Tc of the purification catalyst 35a of the purification device 35 based on the coolant water temperature Tw from the water temperature sensor 15, the engine speed Ne of the engine 12, and the load factor KL.

[0027] In the automobile 10 of the embodiment configured in this way, the electronic control unit 70 sets the target gear stage Gs* of the transmission 54 based on the accelerator opening Acc and the vehicle speed V, and controls the transmission 54 so that the gear stage Gs of the transmission 54 becomes the target gear stage Gs*. Further, based on the accelerator opening Acc, the vehicle speed V, and the gear stage Gs of the transmission 54, the target torque Te* of the engine 12 is set, and intake air amount control, fuel injection control, ignition control, etc. of the engine 12 are performed so that the engine 12 is operated based on the target torque Te*.

[0028] In the automobile 10 of the embodiment, while the vehicle is stopped, when the automatic stop condition is satisfied during the operation of the engine 12, the electronic control unit 70 stops the operation of the engine 12, and when the automatic start condition is satisfied during the stop of the engine 12 due to the satisfaction of the automatic stop condition, the electronic control unit 70 starts the engine 12, thereby executing automatic stop control (so-called idle stop control). As the automatic stop condition, for example, a condition where the accelerator is off and the brake is on is used. As the automatic start condition, for example, a condition where the accelerator is on or the brake is off is used.

[0029] Next, the operation of the automobile 10 of the embodiment configured as described above, particularly the operation when ending a trip (when the ignition switch 80 is turned off and the system stops) and the subsequent operation will be described. FIG. 2 is a first control routine executed by the electronic control unit 70, and FIG. 3 is a second control routine executed by the electronic control unit 70. These will be described in order below.

[0030] The first control routine in FIG. 2 will be described. This routine is executed when the ignition switch 80 is turned off. When the ignition switch 80 is turned off, if the engine 12 is running, the operation of the engine 12 is stopped before starting the execution of this routine, and if the engine 12 is stopped, its stopped state is maintained. Also, when starting the execution of this routine, the opening degree TH of the throttle valve 24v is the opener opening degree THop (the opening degree when the drive current Im of the throttle valve 24v is the value 0).

[0031] When the first control routine in FIG. 2 is executed, the electronic control unit 70 first determines whether or not the freezing condition of the throttle section 24 is satisfied based on the outside air temperature To and the coolant temperature Tw of the engine 12 (Steps S100, S102). Here, as the outside air temperature To, the value detected by the outside air temperature sensor 82 when the ignition switch 80 is turned off is used. As the coolant temperature Tw of the engine 12, the value detected by the water temperature sensor 15 when the ignition switch 80 is turned off is used.

[0032] The freezing condition of the throttle section 24 is a condition where freezing (ice is present) has occurred in the throttle section 24 (for example, between the throttle valve 24v and the throttle body 24b) or freezing may occur later, and it is presumed that the freezing of the throttle section 24 can be released or water can be removed by executing the opening degree increase / decrease control (initial opening degree increase / decrease control, first opening degree increase / decrease control, second opening degree increase / decrease control) described later. Regarding the determination processes of steps S100 and S102, in the embodiment, when the outside air temperature To is equal to or lower than the threshold value To1 and the cooling water temperature Tw is within the upper and lower limit values Twmax and Twmin based on the outside air temperature To, it is determined that the freezing condition of the throttle section 24 is satisfied. When the outside air temperature To is higher than the threshold value To1, or when the outside air temperature To is equal to or lower than the threshold value To1 and the cooling water temperature Tw is outside the range of the upper and lower limit values Twmax and Twmin, it is determined that the freezing condition of the throttle section 24 is not satisfied. The threshold value To1 and the upper and lower limit values Twmax and Twmin are determined in advance by experiments, analyses, machine learning, etc. As the threshold value To1, for example, about -10°C to 0°C is used. As the upper limit value Twmax, for example, about 100°C to 120°C is used. As the lower limit value Twmin, for example, about 0°C to 20°C is used. The upper and lower limit values Twmax and Twmin are determined in advance by experiments, analyses, machine learning, etc. regarding the relationship between the outside air temperature To and the upper and lower limit values Twmax and Twmin, stored as a map for setting the upper and lower limit values, and when the outside air temperature To is equal to or lower than the threshold value To1, when the outside air temperature To is given, the corresponding upper and lower limit values Twmax and Twmin are derived from this map for setting. FIG. 4 is an explanatory diagram showing an example of the map for setting the upper and lower limit values. As shown in the figure, the upper and lower limit values Twmax and Twmin are set such that they become higher as the outside air temperature To becomes lower.

[0033] Here, a mechanism by which freezing occurs between the throttle valve 24v and the throttle body 24b will be described. During operation of the engine 12, moisture blown back from the combustion chamber 29 side to the throttle portion 24 side may be cooled by intake air in a low-temperature environment, adhere to the throttle valve 24v, condense, and freeze. After the engine 12 is stopped, the temperature of the throttle valve 24v increases due to the cooling water flowing through the throttle body 24b, melting the ice, and the water generated by the melting may flow down the lower side of the throttle valve 24v, accumulate between the throttle valve 24v and the throttle body 24b, and be cooled by the outside air and refreeze. In the embodiment, based on this, as described above, it is determined whether or not the freezing condition of the throttle portion 24 is established based on the outside air temperature To and the cooling water temperature Tw of the engine 12. As a result, when the outside air temperature To is relatively high, such as in summer, it is determined that the freezing condition of the throttle portion 24 is not established. In addition, in winter, when the cooling water temperature Tw of the engine 12 is sufficiently low that it is difficult to unfreeze (melt or crack) the throttle section 24 even when the opening increase / decrease control described below is executed, or when the cooling water temperature Tw of the engine 12 is sufficiently high that the throttle section 24 does not freeze in the first place, it will be determined that the freezing conditions for the throttle section 24 are not met.

[0034] When it is determined in steps S100 and S102 that the freezing condition of the throttle section 24 is satisfied, among the opening degree increase / decrease controls for increasing or decreasing the opening degree of the throttle valve 24v, the first-time opening degree increase / decrease control for performing only once the increase / decrease set of increasing and decreasing the opening degree of the throttle valve 24v is executed (step S110), and this routine is terminated. Here, in the first-time opening degree increase / decrease control, the target opening degree TH* of the throttle valve 24v is increased from the opener opening degree THop and then decreased to the opener opening degree THop, and the drive current Im based on this target opening degree TH* is supplied to the throttle motor 24m, thereby controlling the throttle valve 24v. Thereby, it is possible to release the freezing of the throttle section 24 or remove water. For example, when the ignition switch 80 is turned off during the operation stop of the engine 12 due to the establishment of the automatic stop condition, etc., when the ignition switch 80 is turned off, the temperature of the throttle valve 24v rises due to the cooling water flowing through the throttle body 24b, and the ice adhering to the throttle valve 24v may be melted. Therefore, by executing the first-time opening degree increase / decrease control at this time, the water in the throttle section 24 (around the throttle valve 24v) can be removed.

[0035] When it is determined in steps S100 and S102 that the freezing condition of the throttle section 24 is not satisfied, this routine is terminated without executing the opening degree increase / decrease control. Thereby, the opportunity to execute the opening degree increase / decrease control can be limited, and the wasteful power consumption of the battery 52 can be suppressed.

[0036] Next, the second control routine in FIG. 3 will be described. This routine is repeatedly executed every time the soak time (time from the end of the trip) Ts coincides with a multiple of the predetermined time ΔT, that is, every predetermined time ΔT (for example, about several tens of minutes) after the end of the trip, when it is determined by the first control routine in FIG. 2 that the freezing condition of the throttle section 24 is satisfied and the first-time opening degree increase / decrease control is executed (when there is a history). When starting the execution of this routine, the opening degree TH of the throttle valve 24v is the opener opening degree THop.

[0037] When the second control routine of FIG. 3 is executed, the electronic control unit 70 first executes determination control for decreasing the opening degree TH of the throttle valve 24v from the opener opening degree THop (step S200). Here, in the determination control, an opening degree smaller than the opener opening degree THop is set for the target opening degree TH* of the throttle valve 24v over a predetermined time T10 (for example, about several hundred msec), and the throttle valve 24v is controlled by supplying a drive current Im based on this target opening degree TH* to the throttle motor 24m.

[0038] Subsequently, based on the deviation amount (difference) Dth between the opening degree TH and the target opening degree TH* of the throttle valve 24v during the determination control, the drive current Im of the throttle motor 24m, and the opening degree change rate dTH which is the change amount of the opening degree TH of the throttle valve 24v per unit time, it is determined whether or not freezing has occurred between the throttle section 24, particularly between the throttle valve 24v and the throttle body 24b (ice exists and it is difficult to make the opening degree TH of the throttle valve 24v smaller than the opener opening degree THop) (steps S210, S212). Here, the value detected by the throttle position sensor 24o is used as the opening degree TH of the throttle valve 24v. The value detected by the current sensor 24i is used as the drive current Im of the throttle motor 24m.

[0039] Regarding the determination processes in steps S210 and S212, in the embodiment, when at least one of the following first condition, second condition, and third condition is satisfied, it is determined that freezing has occurred between the throttle valve 24v and the throttle body 24b, and when all of the first condition, second condition, and third condition are not satisfied, it is determined that no freezing has occurred between the throttle valve 24v and the throttle body 24b. The first condition, second condition, and third condition are conditions for determining whether or not freezing has occurred between the throttle valve 24v and the throttle body 24b (it is difficult to make the opening TH of the throttle valve 24v smaller than the opener opening THop) by determining whether or not the opening TH of the throttle valve 24v follows the target opening TH* when the drive current Im based on the target opening TH* is supplied to the throttle motor 24m in the determination control. The first condition is a condition in which the state where the deviation amount Dth between the opening TH of the throttle valve 24v and the target opening TH* is equal to or greater than the threshold value Dthref continues for a predetermined time T1 or longer. The second condition is a condition in which the state where the absolute value of the drive current Im of the throttle motor 24m is equal to or greater than the threshold value Imref1 and the absolute value of the opening change rate dTH of the throttle valve 24v is equal to or less than the threshold value dTHref1 continues for a predetermined time T2 or longer. The third condition is a condition in which the state where the absolute value of the drive current Im of the throttle motor 24m is equal to or greater than the threshold value Imref2, which is greater than the threshold value Imref1, continues for a predetermined time T3 or longer. The threshold value Dthref, the threshold value Imref1, the threshold value dTHref1, and the predetermined times T1, T2, and T3 are determined in advance by experiments, analysis, machine learning, etc. As the predetermined times T1, T2, and T3, times slightly shorter than the above-described predetermined time T10 are used. The predetermined times T1, T2, and T3 may be the same time or different times. The threshold value Imref2 is a threshold value for overcurrent determination.

[0040] When it is determined in steps S210 and S212 that freezing has occurred between the throttle valve 24v and the throttle body 24b, the first throttle opening increase / decrease control in FIG. 5 is executed in the throttle opening increase / decrease control (step S220), and this routine ends. On the other hand, when it is determined that no freezing has occurred between the throttle valve 24v and the throttle body 24b, the second throttle opening increase / decrease control in FIG. 6 is executed in the throttle opening increase / decrease control (step S230), and this routine ends. Here, the first throttle opening increase / decrease control is control for releasing the freezing between the throttle valve 24v and the throttle body 24b. The second throttle opening increase / decrease control is control for removing water when water is present in the throttle section 24 (around the throttle valve 24v). Hereinafter, the first throttle opening increase / decrease control in FIG. 5 and the second throttle opening increase / decrease control in FIG. 6 will be described in order.

[0041] The first throttle opening increase / decrease control in FIG. 5 will be described. In the first throttle opening increase / decrease control, the electronic control unit 70 executes throttle opening increase control for increasing the opening of the throttle valve 24v and throttle opening decrease control for decreasing the opening of the throttle valve 24v in this order (steps S300, S310), and counts up the number of times Ns of the increase / decrease set (set of throttle opening increase control and throttle opening decrease control) of the opening TH of the throttle valve 24v (step S320). Here, when starting the first throttle opening increase / decrease control in FIG. 5, the value 0 as an initial value is set for the number of times Ns of the increase / decrease set.

[0042] In the opening increase control, the target opening TH* of the throttle valve 24v is increased to a predetermined opening THu (THop < TH1 < TH2 < THu) that is larger than the opener opening THop, and the drive current Im based on this target opening TH* is supplied to the throttle motor 24m to control the throttle valve 24v. In the embodiment, when starting the opening increase control, the opening TH at the start is set to the initial value of the target opening TH*, and in the start interval where the target opening TH* is less than or equal to the threshold value TH1, the opening increase rate Ru, which is the amount of increase per unit time of the target opening TH*, is set to a predetermined value Ru1 to increase the target opening TH*. Also, in the intermediate interval where the target opening TH* is larger than the threshold value TH1 and less than the threshold value TH2, the opening increase rate Ru is set to a predetermined value Ru2 that is larger than the predetermined value Ru1 to increase the target opening TH*. Further, in the end interval where the target opening TH* is greater than or equal to the threshold value TH2, the opening increase rate Ru is set to the predetermined value Ru1 to increase the target opening TH*.

[0043] In the opening decrease control, the target opening TH* of the throttle valve 24v is decreased to a predetermined opening THd (THd < THop < TH1 < TH2 < THu) that is smaller than the opener opening THop, and the drive current Im based on this target opening TH* is supplied to the throttle motor 24m to control the throttle valve 24v. The reason for decreasing the target opening TH* below the opener opening THop is to release the freezing (break the ice) between the throttle valve 24v and the throttle body 24b. In the embodiment, when starting the opening decrease control, the opening TH at the start is set to the initial value of the target opening TH*, and in the start interval where the target opening TH* is greater than or equal to the threshold value TH2, the opening decrease rate Rd, which is the amount of decrease per unit time of the target opening TH*, is set to a predetermined value Rd1 to decrease the target opening TH*. Also, in the intermediate interval where the target opening TH* is less than the threshold value TH2 and greater than the threshold value TH1, the opening decrease rate Rd is set to a predetermined value Rd2 that is larger than the predetermined value Rd1 to decrease the target opening TH*. Further, in the end interval where the target opening TH* is less than or equal to the threshold value TH1, the opening decrease rate Rd is set to the predetermined value Rd1 to decrease the target opening TH*.

[0044] By performing the opening increase control and the opening decrease control in this way, specifically, by gently changing the target opening TH* of the throttle valve 24v and thus the opening TH in the start interval and the end interval more gently than in the intermediate interval, it is possible to suppress the rattling noise in the gear mechanism connecting the throttle motor 24m and the throttle valve 24v.

[0045] When the opening increase control and the opening decrease control are thus terminated, based on the deviation amount Dth between the opening TH and the target opening TH* of the throttle valve 24v, the drive current Im of the throttle motor 24m, and the opening change rate dTH of the throttle valve 24v during the opening increase control and the opening decrease control, it is determined whether the freezing between the throttle valve 24v and the throttle body 24b has been released (the ice cracking has been completed) (steps S330, S332).

[0046] Here, regarding the determination processes in steps S330 and S332, in the embodiment, when the target opening TH* of the throttle valve 24v is smaller than the opener opening THop in the opening decrease control, when at least one of the above-described first condition, second condition, and third condition is satisfied, it is determined that the freezing between the throttle valve 24v and the throttle body 24b has not been released (the ice cracking has not been completed), and when all of the first condition, second condition, and third condition are not satisfied, it is determined that the freezing between the throttle valve 24v and the throttle body 24b has been released (the ice cracking has been completed). The first condition, second condition, and third condition are conditions for determining whether the freezing between the throttle valve 24v and the throttle body 24b has been released by determining whether the opening TH of the throttle valve 24v follows the target opening TH* when the drive current Im based on the target opening TH* is supplied to the throttle motor 24m when the target opening TH* of the throttle valve 24v is smaller than the opener opening THop in the opening decrease control. By such opening increase control and opening decrease control, the freezing between the throttle valve 24v and the throttle body 24b can be released (the ice can be cracked).

[0047] When it is determined in steps S330 and S332 that the freezing between the throttle valve 24v and the throttle body 24b has been released (the ice breaking has been completed), the number of times Ns of the increase / decrease set is compared with a threshold value Ns1 (step S340). Here, the threshold value Ns1 is determined in advance by experiments, analysis, machine learning, etc. as the number of times at least necessary to release the freezing between the throttle valve 24v and the throttle body 24b (break the ice) and further separate the ice from around the throttle valve 24v. As the threshold value Ns1, for example, about 3 to 5 times is used. When the number of times Ns of the increase / decrease set is less than the threshold value Ns1, the process returns to step S300. When the number of times Ns of the increase / decrease set is equal to or greater than the threshold value Ns1, this routine ends. That is, when the freezing between the throttle valve 24v and the throttle body 24b is released and the number of times Ns of the increase / decrease set is less than the threshold value Ns1, the first opening degree increase / decrease control ends when the number of times Ns of the increase / decrease set reaches the threshold value Ns1 or more. Thereby, it is possible to more sufficiently break the ice between the throttle valve 24v and the throttle body 24b and further separate it from around the throttle valve 24v.

[0048] When it is determined in steps S330 and S332 that the freezing between the throttle valve 24v and the throttle body 24b has not been released (the ice breaking has not been completed), the number of times Ns of the increase / decrease set is compared with a threshold value Ns2 that is greater than the threshold value Ns1 (step S350). Here, the threshold value Ns2 is determined in advance by experiments, analysis, machine learning, etc. as the number of times that can suppress the excessive increase in the power consumption of the battery 52. As the threshold value Ns2, for example, a number about 1 to 3 times more than the threshold value Ns1 is used. When the number of times Ns of the increase / decrease set is less than the threshold value Ns2, the process returns to step S300. When the number of times Ns of the increase / decrease set is equal to or greater than the threshold value Ns2, this routine ends. That is, even if the freezing between the throttle valve 24v and the throttle body 24b has not been released, when the number of times Ns of the increase / decrease set reaches the threshold value Ns2 or more, the first opening degree increase / decrease control ends. Thereby, it is possible to suppress the excessive increase in the power consumption of the battery 52.

[0049] FIG. 7 is a time chart showing an example of the target opening TH* and the opening TH of the throttle valve 24v when it is determined that freezing has occurred between the throttle valve 24v and the throttle body 24b (steps S210 and S212 in FIG. 3) and the first opening increase / decrease control (step S220 in FIG. 3, FIG. 5) is executed. In the example of FIG. 7, the threshold value Ns1 is set to 4 times. As shown in the figure, when determination control is executed and it is determined that freezing has occurred between the throttle valve 24v and the throttle body 24b based on the deviation amount Dth, the drive current Im, and the opening change rate dTH at that time (times t11 to t12), the first opening increase / decrease control is started. Then, when the number of increase / decrease sets Ns is less than 4 times or it is determined that the freezing between the throttle valve 24v and the throttle body 24b has not been released (the ice cracking is not completed), the first opening increase / decrease control is continued. And when it is determined that the number of increase / decrease sets Ns is 4 times or more and the freezing between the throttle valve 24v and the throttle body 24b has been released (the ice cracking is completed) (time t13), the first opening increase / decrease control is terminated. In this way, the freezing between the throttle valve 24v and the throttle body 24b can be released (the ice can be cracked).

[0050] Next, the second opening increase / decrease control in FIG. 6 will be described. In the second opening increase / decrease control, the electronic control unit 70 executes the opening increase control and the opening decrease control in this order (steps S400 and S410) in the same manner as the processes in steps S300 to S320 of the first opening increase / decrease control in FIG. 5, and counts up the number of increase / decrease sets Ns (step S420). Here, when the second opening increase / decrease control in FIG. 6 is started, the value 0 as the initial value is set for the number of increase / decrease sets Ns.

[0051] Next, the number of times Ns of the increase / decrease set is compared with a threshold value Ns3 (step S430). Here, the threshold value Ns3 is determined in advance by experiments, analysis, machine learning, etc. as the number of times required to remove water when water is present around the throttle section 24 (around the throttle valve 24v). As the threshold value Nref3, for example, about 2 to 4 times is used. When the number of times Ns of the increase / decrease set is less than the threshold value Ns3, the process returns to step S400. When the number of times Ns of the increase / decrease set is equal to or greater than the threshold value Ns3, this routine ends. That is, when the number of times Ns of the increase / decrease set reaches the threshold value Ns3 or more, the second opening degree increase / decrease control ends. In this way, when water is present around the throttle valve 24v, the water can be removed.

[0052] FIG. 8 is a time chart showing an example of the target opening degree TH* and the opening degree TH of the throttle valve 24v when it is determined that no freezing has occurred between the throttle valve 24v and the throttle body 24b (steps S210 and S212 in FIG. 3) and the second opening degree increase / decrease control (step S230 in FIG. 3, FIG. 6) is executed. In the example of FIG. 8, the threshold value Ns3 is set to 3 times. As shown in the figure, when it is determined that no freezing has occurred between the throttle valve 24v and the throttle body 24b based on the deviation amount Dth, the drive current Im, and the opening degree change rate dTH during the execution of the determination control (times t21 to t22), the second opening degree increase / decrease control is started. Then, when the number of times Ns of the increase / decrease set reaches 3 times or more (time t23), the second opening degree increase / decrease control ends. In this way, when water is present around the throttle valve 24v, the water can be removed.

[0053] FIG. 9 is a time chart showing an example of the state after the trip ends. In FIG. 9, the state of the ignition switch 80, the engine speed Ne of the engine 12, the soak time Ts, and the target opening TH* of the throttle valve 24v are illustrated. As shown in the figure, when the ignition switch 80 is turned off during the operation of the engine 12 (at time t31), the operation of the engine 12 is stopped, and if it is determined that the freezing condition of the throttle section 24 is satisfied based on the outside air temperature To and the coolant temperature Tw at that time, the first opening degree increase / decrease control is executed. Subsequently, when the soak time Ts reaches time ΔT, 2×ΔT, 3×ΔT (at times t32, t33, t34), if it is determined that no freezing has occurred between the throttle valve 24v and the throttle body 24b, the second opening degree increase / decrease control is executed. Thereby, when water exists around the throttle valve 24v, the water can be removed. Then, when the soak time Ts reaches time 4×ΔT (at time t35), if it is determined that freezing has occurred between the throttle valve 24v and the throttle body 24b, the first opening degree increase / decrease control is executed. Thereby, the freezing between the throttle valve 24v and the throttle body 24b can be released (the ice can be broken). In this way, by executing the opening degree increase / decrease control (any one of the first opening degree increase / decrease control, the second opening degree increase / decrease control, and the first opening degree increase / decrease control) at the end of the trip and every predetermined time ΔT thereafter, compared with the case where the opening degree increase / decrease control is executed only at the end of the trip or only when starting the engine 12 during the trip, between trips of the vehicle, the removal of water around the throttle valve 24v and the release of freezing (breaking of ice) between the throttle valve 24v and the throttle body 24b can be performed more sufficiently. That is, between trips of the vehicle, it is possible to more suppress the occurrence of freezing or the progression of the degree of freezing between the throttle valve 24v and the throttle body 24b when freezing has occurred or is occurring.

[0054] Note that by more thoroughly performing the release of the freezing of the throttle unit 24 and the removal of water between trips of the vehicle, the necessity of executing the opening degree increase / decrease control when starting the engine 12 in the next trip is reduced. When the opening degree increase / decrease control is executed when starting the engine 12, although the amount of air inhaled into the combustion chamber 29 fluctuates and may affect the startability of the engine 12, by reducing the necessity of executing the opening degree increase / decrease control when starting the engine 12, such inconveniences can be suppressed from occurring.

[0055] In the automobile 10 of the embodiment described above, when the freezing condition of the throttle unit 24 is satisfied when ending a trip, when ending the trip, the first opening degree increase / decrease control among the opening degree increase / decrease controls is executed, and thereafter, every predetermined time ΔT, the first opening degree increase / decrease control or the second opening degree increase / decrease control among the opening degree increase / decrease controls is executed. Thereby, compared with a case where the opening degree increase / decrease control is executed only when ending a trip or only when starting the engine 12 during a trip, between trips of the vehicle, the release of the freezing (breaking of ice) between the throttle valve 24v and the throttle body 24b and the removal of water around the throttle valve 24v can be performed more thoroughly. That is, between trips of the vehicle, it is possible to more suppress the occurrence of freezing between the throttle valve 24v and the throttle body 24b or the progression of the degree of freezing if it has occurred.

[0056] In the automobile 10 of the embodiment, as the freezing condition of the throttle unit 24, a condition is used where freezing has occurred in the throttle unit 24 or freezing may occur later and the execution of opening degree increase / decrease control (initial opening degree increase / decrease control, first opening degree increase / decrease control, second opening degree increase / decrease control) can presumably release the freezing of the throttle unit 24 or remove water. Specifically, when the outside air temperature To is equal to or lower than the threshold value To1 and the coolant water temperature Tw is within the range of the upper and lower limit values Twmax and Twmin based on the outside air temperature To, it is determined that the freezing condition of the throttle unit 24 is established. When the outside air temperature To is higher than the threshold value To1, or when the outside air temperature To is equal to or lower than the threshold value To1 and the coolant water temperature Tw is outside the range of the upper and lower limit values Twmax and Twmin, it is determined that the freezing condition of the throttle unit 24 is not established. However, as the freezing condition of the throttle unit 24, a condition where freezing has occurred in the throttle unit 24 or freezing may occur later may also be used. That is, as the freezing condition of the throttle unit 24, a condition that does not include the possibility of releasing the freezing of the throttle unit 24 or removing water by executing the opening degree increase / decrease control may also be used. In this case, when the outside air temperature To is equal to or lower than the threshold value To1 and the coolant water temperature Tw is within the range equal to or lower than the upper limit value Twmax based on the outside air temperature To, it is determined that the freezing condition of the throttle unit 24 is established. When the outside air temperature To is higher than the threshold value To1, or when the outside air temperature To is equal to or lower than the threshold value To1 and the coolant water temperature Tw is higher than the upper and lower limit values Twmax, it is determined that the freezing condition of the throttle unit 24 is not established.

[0057] In the automobile 10 of the embodiment, when it is determined that the freezing condition of the throttle unit 24 is established when ending a trip, the initial opening degree increase / decrease control among the opening degree increase / decrease controls is executed when ending the trip. However, the second opening degree increase / decrease control among the opening degree increase / decrease controls may also be executed.

[0058] In the automobile 10 of the embodiment, although the electronic control unit 70 is assumed to be operating even after the end of a trip, it enters a sleep state when the first opening increase / decrease control ends. Thereafter, it may automatically start every predetermined time ΔT to execute the second control routine in FIG. 3, and enter a sleep state when this second control routine ends.

[0059] In the automobile 10 of the embodiment, when the freezing condition of the throttle section 24 is satisfied at the end of a trip, determination control is executed every predetermined time after the end of the trip to determine whether freezing has occurred between the throttle valve 24v and the throttle body 24b. When it is determined that freezing has occurred between the throttle valve 24v and the throttle body 24b, the first opening increase / decrease control is executed. On the other hand, when it is determined that no freezing has occurred between the throttle valve 24v and the throttle body 24b, the second opening increase / decrease control is executed. However, it may be configured to execute the same opening increase / decrease control, for example, the second opening increase / decrease control, without performing the determination control.

[0060] In the automobile 10 of the embodiment, it is determined whether freezing has occurred between the throttle valve 24v and the throttle body 24b by using the first condition, the second condition, and the third condition based on the deviation amount Dth between the opening TH of the throttle valve 24v and the target opening TH* during the determination control, the drive current Im of the throttle motor 24m, and the opening change rate dTH of the throttle valve 24v. However, it may be configured to determine whether freezing has occurred between the throttle valve 24v and the throttle body 24b by using only a part of the first condition, the second condition, and the third condition.

[0061] In the automobile 10 of the embodiment, based on the deviation amount Dth, drive current Im, and opening change rate dTH during the first opening increase / decrease control, the first condition, the second condition, and the third condition are used to determine whether the freezing between the throttle valve 24v and the throttle body 24b has been released. However, it is also possible to determine whether the freezing between the throttle valve 24v and the throttle body 24b has been released by using only a part of the first condition, the second condition, and the third condition.

[0062] In the automobile 10 of the embodiment, during the first opening increase control, as the opening increase control, the target opening TH* of the throttle valve 24v and thus the opening TH are increased, and then, as the opening decrease control, the target opening TH* of the throttle valve 24v and thus the opening TH are decreased. Here, when it is determined that the throttle valve 24v has bitten into a foreign object (for example, ice, etc.) while the target opening TH* of the throttle valve 24v and thus the opening TH are increasing, the target opening TH* of the throttle valve 24v and thus the opening TH may be decreased by a predetermined opening ΔTH1 and then the increase may be resumed. Also, when it is determined that the throttle valve 24v has bitten into a foreign object while the target opening TH* of the throttle valve 24v and thus the opening TH are decreasing, the target opening TH* of the throttle valve 24v and thus the opening TH may be increased by a predetermined opening ΔTH2 and then the decrease may be resumed. By such control, when the throttle valve 24v has bitten into a foreign object, the biting can be released. The predetermined openings ΔTH1 and ΔTH2 are determined in advance by experiments, analyses, machine learning, etc. as values necessary to release the biting of the foreign object bitten by the throttle valve 24v. The predetermined openings ΔTH1 and ΔTH2 may be the same value or different values.

[0063] Regarding the determination process of whether the throttle valve 24v has bitten into foreign matter, based on the drive current Im of the throttle motor 24m and the opening change rate dTH of the throttle valve 24v during the opening increase control or the opening decrease control, when at least one of the following fourth condition and fifth condition is satisfied, it is determined that the throttle valve 24v has bitten into foreign matter, and when all of the fourth condition and fifth condition are not satisfied, it is determined that the throttle valve 24v has not bitten into foreign matter. The fourth condition and the fifth condition are conditions for determining whether the throttle valve 24v has bitten into foreign matter by determining whether the opening TH of the throttle valve 24v follows the target opening TH* when the drive current Im based on the target opening TH* is supplied to the throttle motor 24m. The fourth condition is a condition in which a state where the absolute value of the drive current Im of the throttle motor 24m is equal to or greater than the threshold value Imref3 and the absolute value of the opening change rate dTH of the throttle valve 24v is equal to or less than the threshold value dTHref2 continues for a predetermined time T4 or more. The fifth condition is a condition in which a state where the absolute value of the drive current Im of the throttle motor 24m is equal to or greater than a threshold value Imref4 that is greater than the threshold value Imref3 continues for a predetermined time T5 or more. The threshold value Imref3, the threshold value dTHref2, and the predetermined times T4 and T5 are determined in advance by experiments, analysis, machine learning, etc. The threshold value Imref3 may be the same value as the above-mentioned threshold value Imref1 or a different value. The threshold value dTHref2 may be the same value as the above-mentioned threshold value dTHref1 or a different value. The predetermined time T4 may be the same time as the above-mentioned predetermined time T2 or a different time. The predetermined time T5 may be the same time as the above-mentioned predetermined time T3 or a different time. The threshold value Imref4 is a threshold value for overcurrent determination, similar to the above-mentioned threshold value Imref2.

[0064] FIG. 10 is a time chart showing the target opening TH* and the opening TH of the throttle valve 24v when the throttle valve 24v has bitten into a foreign object while increasing the target opening TH* and thus the opening TH in the first opening increase / decrease control. As shown in the figure, when it is determined that the throttle valve 24v has bitten into a foreign object based on the drive current Im or the opening change rate dTH while increasing the target opening TH* and thus the opening TH of the throttle valve 24v (time t41), the target opening TH* and thus the opening TH of the throttle valve 24v are decreased (time t41 to t42) and then the increase is resumed (time t42 to...). By such control, when the throttle valve 24v has bitten into a foreign object, the biting can be released.

[0065] FIG. 11 is a time chart showing the target opening TH* and the opening TH of the throttle valve 24v when the throttle valve 24v has bitten into a foreign object while decreasing the target opening TH* and thus the opening TH in the first opening increase / decrease control. As shown in the figure, when it is determined that the throttle valve 24v has bitten into a foreign object based on the drive current Im or the opening change rate dTH while decreasing the target opening TH* and thus the opening TH of the throttle valve 24v (time t51), the target opening TH* and thus the opening TH of the throttle valve 24v are increased (time t51 to t52) and then the increase is resumed (time t52 to...). By such control, when the throttle valve 24v has bitten into a foreign object, the biting can be released.

[0066] In the modification, it is determined whether the throttle valve 24v has bitten into a foreign object using the fourth condition and the fifth condition based on the drive current Im and the opening change rate dTH during the opening increase / decrease control or the opening decrease control. However, it may be determined whether the throttle valve 24v has bitten into a foreign object using only either the fourth condition or the fifth condition.

[0067] In the modified example, when it is determined that the throttle valve 24v has bitten into a foreign object while increasing the target opening degree TH* and thus the opening degree TH of the throttle valve 24v, the target opening degree TH* and thus the opening degree TH of the throttle valve 24v are decreased by a predetermined opening degree ΔTH1 and then the increase is resumed. Also, when it is determined that the throttle valve 24v has bitten into a foreign object while decreasing the target opening degree TH* and thus the opening degree TH of the throttle valve 24v, the target opening degree TH* and thus the opening degree TH of the throttle valve 24v are increased by a predetermined opening degree ΔTH2 and then the decrease is resumed. However, when the number of determinations that the throttle valve 24v has bitten into a foreign object reaches a predetermined number or more (the determination frequency is relatively high), it may be possible to abort the first opening degree increase / decrease control. This is because there may be an abnormality in the throttle valve 24v.

[0068] In the motor vehicle 10 of the embodiment, in the first opening degree increase control, when the freezing between the throttle valve 24v and the throttle body 24b is released and the number of increase / decrease sets Ns is less than the threshold value Ns1, the first opening degree increase / decrease control is terminated when the number of increase / decrease sets Ns reaches the threshold value Ns1 or more. However, when the freezing between the throttle valve 24v and the throttle body 24b is released, even when the number of increase / decrease sets Ns is less than the threshold value Ns1, it may be possible to terminate the first opening degree increase / decrease control.

[0069] In the motor vehicle 10 of the embodiment, in the first opening degree increase / decrease control, even if the freezing between the throttle valve 24v and the throttle body 24b has not been released, when the number of increase / decrease sets Ns reaches the threshold value Ns2 or more, the first opening degree increase / decrease control is terminated. However, it may be possible to execute the first opening degree increase / decrease control until the freezing between the throttle valve 24v and the throttle body 24b is released.

[0070] In the automobile 10 of the embodiment, in the opening increase control and the opening decrease control of the first opening increase / decrease control and the second opening increase / decrease control, the target opening TH* of the throttle valve 24v and thus the opening TH are gradually changed in the start section and the end section more than in the intermediate section. However, regardless of the start section, the intermediate section, and the end section, the target opening TH* of the throttle valve 24v and thus the opening TH may be changed at a substantially constant speed (the change rate which is the amount of change per unit time).

[0071] In the automobile 10 of the embodiment, the opening increase control and the opening decrease control are the same for the first opening increase / decrease control and the second opening increase / decrease control, but the opening increase control and / or the opening decrease control may be made different. For example, in the first opening increase / decrease control and the second opening increase / decrease control, one of the threshold values TH1, TH2 and the predetermined values Ru1, Ru2 used in the opening increase control and the threshold values TH2, TH1 and the predetermined values Rd1, Rd2 used in the opening decrease control may be made different from each other.

[0072] In the automobile 10 of the embodiment, in the opening increase control of the first opening increase / decrease control and the second opening increase / decrease control, the opening increase rate Ru in the start section and the opening increase rate Ru in the end section are set to the same predetermined value Ru1, but they may be different from each other. Also, in the embodiment, in the opening decrease control of the first opening increase / decrease control and the second opening increase / decrease control, the opening decrease rate Rd in the start section and the opening decrease rate Rd in the end section are set to the same predetermined value Rd1, but they may be different from each other.

[0073] In the automobile 10 of the embodiment, in the first opening increase / decrease control and the second opening increase / decrease control, the boundary opening between the start section and the intermediate section of the opening increase control and the boundary opening between the intermediate section and the end section of the opening decrease control are set to the same threshold value TH1, but they may be different from each other. Also, in the embodiment, in the first opening increase / decrease control and the second opening increase / decrease control, the boundary opening between the intermediate section and the end section of the opening increase control and the boundary opening between the start section and the intermediate section of the opening decrease control are set to the same threshold value TH2, but they may be different from each other.

[0074] In the embodiment, a general form of the motor vehicle 10 that travels using the power from the engine 12 was described. However, it may be in the form of a series-type or parallel-type hybrid vehicle equipped with at least one motor generator in addition to the engine.

[0075] The correspondence between the main elements of the embodiment and the main elements of the invention described in the column of means for solving the problems will be described. In the embodiment, the engine 12 corresponds to the "engine", and the electronic control unit 70 corresponds to the "control device".

[0076] Note that the correspondence between the main elements of the embodiment and the main elements of the invention described in the column of means for solving the problems is an example for specifically explaining the form for implementing the invention described in the column of means for solving the problems in the embodiment. Therefore, it does not limit the elements of the invention described in the column of means for solving the problems. That is, the interpretation of the invention described in the column of means for solving the problems should be made based on the description in that column, and the embodiment is merely a specific example of the invention described in the column of means for solving the problems.

[0077] As described above, the embodiments have been used to explain the form for implementing the present invention. However, the present invention is not limited to such embodiments, and it goes without saying that the present invention can be implemented in various forms without departing from the gist of the present invention.

Industrial Applicability

[0078] The present invention can be used in the vehicle manufacturing industry and the like.

Explanation of Reference Numerals

[0079] 10 Automobile, 12 Engine, 14 Crankshaft, 14a Crank Position Sensor, 15 Water Temperature Sensor, 16 Cam Position Sensor, 22 Air Cleaner, 23 Intake Passage, 23a Air Flow Meter, 23t Temperature Sensor, 24 Throttle Section, 24b Throttle Body, 24i Current Sensor, 24m Throttle Motor, 24o Throttle Position Sensor, 24v Throttle Valve, 26 In-Cylinder Injection Valve, 28 Intake Valve, 29 Combustion Chamber, 30 Spark Plug, 32 Piston, 33 Exhaust Valve, 34 Exhaust Pipe, 35 Purification Device, 35a Purification Catalyst, 37 Front Air-Fuel Ratio Sensor, 38 Rear Air-Fuel Ratio Sensor, 50 Generator, 51 Power Line, 52 Battery, 54 Transmission, 70 Electronic Control Unit, 71 CPU, 72 ROM, 73 RAM, 74 Flash Memory, 80 Ignition Switch, 82 Outside Air Temperature Sensor.

Claims

1. An engine comprising a throttle section having a throttle body provided in an intake passage and a throttle valve rotatably supported by the throttle body, a control device for controlling the engine, A vehicle comprising: When the freezing condition of the throttle section is satisfied when ending a trip, the control device executes opening degree increase / decrease control for increasing and decreasing the opening degree of the throttle valve at the time of ending the trip and at each predetermined time thereafter, The control device, At each predetermined time after the end of the trip, Before executing the opening degree increase / decrease control, determination control for decreasing the opening degree of the throttle valve is executed, Based on at least one of the deviation amount between the opening degree of the throttle valve and the target opening degree, the drive current of the throttle motor that adjusts the opening degree of the throttle valve, and the opening degree change rate which is the change amount of the opening degree of the throttle valve per unit time, it is determined whether or not the throttle section is frozen, When it is determined that the throttle section is frozen, first opening degree increase / decrease control is executed as the opening degree increase / decrease control, When it is determined that the throttle section is not frozen, second opening degree increase / decrease control different from the first opening degree increase / decrease control is executed as the opening degree increase / decrease control, Vehicle.

2. The vehicle according to claim 1, The control device, When at least one of a first condition in which a state where the deviation amount is equal to or greater than a predetermined deviation amount continues for a first predetermined time or more, a second condition in which an absolute value of the drive current is equal to or greater than a first predetermined current and an absolute value of the opening degree change rate is equal to or less than a predetermined change rate continues for a second predetermined time or more, and a third condition in which a state where the absolute value of the drive current is equal to or greater than a second predetermined current greater than the first predetermined current continues for a third predetermined time or more is satisfied, it is determined that the throttle section is frozen, When none of the first condition, the second condition, and the third condition is satisfied, it is determined that the throttle section is not frozen, Vehicle.

3. The vehicle according to claim 1, The control device, In the first opening degree increase / decrease control, an increase / decrease set for increasing and then decreasing the opening degree of the throttle valve is executed until it is determined that the freezing of the throttle section has been released, In the second opening degree increase / decrease control, the increase / decrease set is executed a predetermined number of times, Vehicle.

4. The vehicle according to claim 3, wherein the control device determines that the freezing of the throttle part is released when all of a first condition that a state where the deviation amount is equal to or greater than a predetermined deviation amount continues for a first predetermined time or longer, a second condition that a state where the absolute value of the drive current is equal to or greater than a first predetermined current and the absolute value of the opening change rate is equal to or less than a predetermined change rate continues for a second predetermined time or longer, and a third condition that a state where the absolute value of the drive current is equal to or greater than a second predetermined current greater than the first predetermined current continues for a third predetermined time or longer are not satisfied. Vehicle.

5. The vehicle according to claim 3, wherein the throttle valve operates using power from a battery, in the first opening increase / decrease control, the control device when it is determined that the freezing of the throttle part is released, if the number of times of the increase / decrease set is less than a first predetermined number of times, when the number of times of the increase / decrease set reaches the first predetermined number of times, ends the first opening increase / decrease control, even if it is not determined that the freezing of the throttle part is released, when the number of times of the increase / decrease set reaches a second predetermined number of times greater than the first predetermined number of times, ends the first opening increase / decrease control. Vehicle.

6. The vehicle according to claim 1, wherein in the first opening increase / decrease control, when the control device determines that the throttle valve has bitten into a foreign object while performing either an increase or a decrease in the opening of the throttle valve, after performing the other one different from the either one of the increase and decrease in the opening of the throttle valve, resumes the either one. Vehicle.

7. The vehicle according to claim 6, wherein the control device determines that the throttle valve has bitten into a foreign object when at least one of a fourth condition that a state where the absolute value of the drive current is equal to or greater than a third predetermined current and the absolute value of the opening change rate is equal to or less than a second predetermined change rate continues for a fourth predetermined time or longer and a fifth condition that a state where the absolute value of the drive current is equal to or greater than a fourth predetermined current greater than the third predetermined current continues for a fifth predetermined time or longer is satisfied. Vehicle.

8. The vehicle according to claim 1, wherein in the opening increase / decrease control, the control device gently increases or decreases the opening of the throttle valve in the start section and the end section of the increase or decrease in the opening of the throttle valve rather than in the intermediate section between the start section and the end section. Vehicle.

9. A vehicle according to claim 1, wherein the freezing condition is a condition that when ending the trip, the coolant temperature of the engine is within a water temperature range based on the outside air temperature. Vehicle.

Images