JP2009191728A - Control device for engine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent the occurrence of hunting in a determination result of whether or not an engine is in an idling state. <P>SOLUTION: An idling determination part 8106 of ECU 8000 determines that the engine is not in the idling state if throttle opening is not less than a first threshold TA(1), and determines that the engine is in the idling state if the throttle opening is not greater than a second threshold TA(2) or smaller. A target value setting part 8108, sets a target throttle opening TAT according to an accelerator opening and an engine rotation speed NE. A restriction part 8110 restricts the throttle opening so as to keep the target throttle opening TAT not less than the first threshold TA(1) and not greater than the second threshold TA(2) if fluctuation quantity of the accelerator opening is not greater than a predetermined value. A control part 8112 controls an electronic throttle valve so as to keep the throttle opening at the target throttle valve opening TAT. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an engine control device, and more particularly to a technique for controlling an engine so that hunting between determination that the engine is in an idle state and determination that the engine is not in an idle state does not occur.

  Conventionally, an engine whose output is determined by the throttle opening is known. Generally, the throttle opening operates so as to uniquely correspond to the accelerator opening. However, if the throttle opening and the accelerator opening always correspond uniquely, it is difficult to control the driving force of the vehicle regardless of the driver's intention, for example, when the behavior of the vehicle is disturbed. It is. Therefore, there is a vehicle provided with an electronic throttle valve that is operated by an actuator so that the output can be controlled without depending on the accelerator opening. In a vehicle equipped with an electronic throttle valve, the target engine torque is set based on the behavior of the vehicle in addition to the accelerator opening, and the engine is controlled so that the actual engine torque becomes the set target engine torque. It is possible.

  Japanese Patent Laying-Open No. 2005-233088 (Patent Document 1) is based on a required torque setting unit that sets a torque required for an engine for each calculation cycle based on an engine operating state and an accelerator opening, and an amount of change in the accelerator opening. An accelerator opening speed setting unit that sets the accelerator opening speed and a basic change amount limit value that limits the change amount of the required torque based on the engine operating state are set, and the basic change amount limit value is corrected by the accelerator opening speed. A torque change amount limit value setting unit for setting a torque change amount limit value, a target torque setting unit for setting a target torque to be obtained from the engine by adding the torque change amount limit value to the request torque set at the previous calculation, An electronic control slot comprising a target throttle opening setting unit for setting a target throttle opening of the electronic throttle valve so that a target torque is generated It discloses an apparatus.

According to the electronically controlled throttle device described in this publication, since the accelerator opening speed gain set based on the change amount of the accelerator opening is added to the torque change amount limit value, the accelerator opening amount is small. However, if the accelerator opening is changed quickly, a sharp acceleration performance can be obtained, and the driver will not feel rattling. On the other hand, if the accelerator opening is changed slowly, the torque level difference will be reduced. The associated torque shock can be alleviated and good running performance can be obtained.
Japanese Patent Laying-Open No. 2005-233088

  When the target engine torque is set by using other parameters in addition to the accelerator opening as in the electronically controlled throttle device described in Japanese Patent Application Laid-Open No. 2005-233088, the throttle opening is reduced even if the accelerator opening is constant. Can change. Therefore, if it is determined from the throttle opening whether the engine is in an idle state, even if the accelerator opening is constant, the determination result as to whether the engine is in an idle state can be hunted.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide an engine control device that can stabilize the determination result of whether or not the engine is in an idle state. It is.

  In the engine control apparatus according to the first aspect of the present invention, the means for detecting the accelerator opening, the means for detecting the engine output shaft rotational speed, the accelerator opening and the engine output shaft rotational speed Means for setting a target value of the value indicating the engine operating state, means for controlling the engine so that the value indicating the engine operating state becomes the target value, and a value indicating the engine operating state. Means for detecting, first determination means for determining that the engine is not in an idle state when a value indicating the engine operating state is in the first region, and a value indicating the engine operating state is the second A second determination means for determining that the engine is in an idle state when the engine is in an area of the engine, and if the amount of change in the accelerator opening is equal to or less than a predetermined value, the target value is 2 And a limiting means for limiting to be in either one area of the region.

  According to this configuration, a target value of a value (for example, throttle opening or engine torque) indicating the operating state of the engine is set according to the accelerator opening and the engine output shaft speed. The engine is controlled so that a value indicating the operating state of the engine becomes a target value. When the value indicating the engine operating state is in the first region, it is determined that the engine is not in the idle state, and when the value indicating the engine operating state is in the second region, it is determined that the engine is in the idle state. The When the amount of change in the accelerator opening is equal to or less than a predetermined value, the target value is limited to be in one of the first region and the second region. Thereby, when the accelerator opening is substantially constant, the value indicating the operating state of the engine changes from the first region to the second region, or changes from the second region to the first region. You can avoid it. Therefore, it is possible to provide an engine control device that can stabilize the determination result of whether or not the engine is in an idle state.

  In the engine control apparatus according to the second invention, in addition to the configuration of the first invention, the limiting means determines that the amount of change in the accelerator opening is equal to or less than a predetermined value and the engine is not in an idle state. If so, the means for limiting the target value to be in the first region, the fluctuation amount of the accelerator opening is not more than a predetermined value, and it is determined that the engine is in an idle state. And means for limiting the target value to be in the second region.

  According to this configuration, if the amount of change in the accelerator opening is equal to or less than a predetermined value and it is determined that the engine is not in an idle state, the target value is limited to be in the first region. If the fluctuation amount of the accelerator opening is equal to or less than a predetermined value and it is determined that the engine is in an idle state, the target value is limited to be in the second region. Thereby, when the accelerator opening is substantially constant, the determination result as to whether or not the engine is in an idle state can be prevented from changing.

  In the engine control apparatus according to the third invention, in addition to the configuration of the first or second invention, the engine is provided with a throttle valve. The value indicating the operating state of the engine is the throttle opening.

  According to this configuration, by limiting the target value of the throttle opening, it is possible to stabilize the determination result as to whether or not the engine is in an idle state.

  In the engine control apparatus according to the fourth invention, in addition to the configuration of the first or second invention, the value indicating the operation state of the engine is the output torque of the engine.

  According to this configuration, by limiting the target value of the output torque of the engine, it is possible to stabilize the determination result as to whether or not the engine is in an idle state.

  In the engine control apparatus according to the fifth aspect of the invention, in addition to the configuration of the third or fourth aspect of the invention, the first area is an area equal to or greater than the first threshold value. The second region is a region equal to or smaller than a second threshold value that is smaller than the first threshold value.

  According to this configuration, it can be determined that the engine is not in the idle state when the throttle opening or the engine output torque is greater than or equal to the first threshold. If the throttle opening or the engine output torque is less than or equal to the second threshold, it can be determined that the engine is not in an idle state.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following description, the same parts are denoted by the same reference numerals. Their names and functions are also the same. Therefore, detailed description thereof will not be repeated.

<First Embodiment>
A vehicle equipped with a control device according to a first embodiment of the present invention will be described with reference to FIG. This vehicle is an FR (Front engine Rear drive) vehicle. A vehicle other than FR may be used.

  The vehicle includes an engine 1000, an automatic transmission 2000, a torque converter 2100, a planetary gear unit 3000 that forms part of the automatic transmission 2000, a hydraulic circuit 4000 that forms part of the automatic transmission 2000, a propeller shaft 5000, A differential gear 6000, a rear wheel 7000, and an ECU (Electronic Control Unit) 8000 are included.

  Engine 1000 is an internal combustion engine that burns a mixture of fuel and air injected from an injector (not shown) in a combustion chamber of a cylinder. The piston in the cylinder is pushed down by the combustion, and the crankshaft is rotated. The auxiliary power 1004 such as an alternator and an air conditioner is driven by the driving force of the engine 1000. A motor may be used as a power source instead of or in addition to engine 1000.

  Automatic transmission 2000 is connected to engine 1000 via torque converter 2100. Automatic transmission 2000 shifts the rotational speed of the crankshaft to a desired rotational speed by forming a desired gear stage. Instead of the automatic transmission that forms the gear stage, CVT (Continuously Variable Transmission) that changes the gear ratio steplessly may be mounted. Furthermore, you may make it mount the automatic transmission which consists of a constant-meshing-type gearwheel speed-changed by a hydraulic actuator or an electric motor.

  The driving force output from automatic transmission 2000 is transmitted to left and right rear wheels 7000 via propeller shaft 5000 and differential gear 6000.

  The ECU 8000 includes a position switch 8006 of a shift lever 8004, an accelerator opening sensor 8010 of an accelerator pedal 8008, an air flow meter 8012, a throttle opening sensor 8018 of an electronic throttle valve 8016, an engine speed sensor 8020, and an input shaft. A rotational speed sensor 8022, an output shaft rotational speed sensor 8024, an oil temperature sensor 8026, and a water temperature sensor 8028 are connected via a harness or the like.

  The position (position) of shift lever 8004 is detected by position switch 8006, and a signal representing the detection result is transmitted to ECU 8000. Corresponding to the position of the shift lever 8004, the gear stage of the automatic transmission 2000 is automatically formed. Further, a manual shift mode in which the driver can select an arbitrary gear stage may be selected according to the driver's operation.

  Accelerator opening sensor 8010 detects the opening of accelerator pedal 8008 (hereinafter also referred to as accelerator opening), and transmits a signal representing the detection result to ECU 8000. Air flow meter 8012 detects the amount of air taken into engine 1000 and transmits a signal representing the detection result to ECU 8000.

  Throttle opening sensor 8018 detects the opening of electronic throttle valve 8016 (hereinafter also referred to as throttle opening) whose opening is adjusted by the actuator, and transmits a signal representing the detection result to ECU 8000. Electronic throttle valve 8016 adjusts the amount of air taken into engine 1000 (output of engine 1000).

  Instead of or in addition to the electronic throttle valve 8016, the amount of air drawn into the engine 1000 can be reduced by changing the lift amount of the intake valve (not shown) or the exhaust valve (not shown) and the opening / closing phase. You may make it adjust.

  Engine speed sensor 8020 detects the speed of the output shaft (crankshaft) of engine 1000 (hereinafter also referred to as engine speed NE), and transmits a signal representing the detection result to ECU 8000. Input shaft rotational speed sensor 8022 detects input shaft rotational speed NI of automatic transmission 2000 (turbine rotational speed NT of torque converter 2100), and transmits a signal representing the detection result to ECU 8000. Output shaft rotational speed sensor 8024 detects output shaft rotational speed NO of automatic transmission 2000 and transmits a signal representing the detection result to ECU 8000.

  Oil temperature sensor 8026 detects the temperature (oil temperature) of oil (ATF: Automatic Transmission Fluid) used for the operation and lubrication of automatic transmission 2000, and transmits a signal indicating the detection result to ECU 8000.

  Water temperature sensor 8028 detects the temperature (water temperature) of cooling water for engine 1000 and transmits a signal representing the detection result to ECU 8000.

  ECU 8000 includes position switch 8006, accelerator opening sensor 8010, air flow meter 8012, throttle opening sensor 8018, engine speed sensor 8020, input shaft speed sensor 8022, output shaft speed sensor 8024, oil temperature sensor 8026, and water temperature sensor. Based on a signal sent from 8028 or the like, a map stored in a ROM (Read Only Memory) 8002 and a program, the devices are controlled so that the vehicle is in a desired running state. The program executed by ECU 8000 may be recorded on a recording medium such as a CD (Compact Disc) or a DVD (Digital Versatile Disc) and distributed to the market.

  In the present embodiment, ECU 8000 has the forward 1st to 8th gears when the shift lever 8004 is in the D (drive) position and the D (drive) range is selected as the shift range of automatic transmission 2000. Automatic transmission 2000 is controlled so that one of these gears is formed. The automatic transmission 2000 can transmit a driving force to the rear wheel 7000 by forming any one of the first to eighth forward gears. In the D range, it may be possible to form a higher gear than the eighth gear. The gear stage to be formed is determined based on a shift diagram created in advance by experiments or the like using the vehicle speed and the accelerator opening as parameters. Note that the ECU may be divided into a plurality of ECUs.

  The planetary gear unit 3000 will be described with reference to FIG. Planetary gear unit 3000 is connected to a torque converter 2100 having an input shaft 2102 coupled to the crankshaft.

  The planetary gear unit 3000 includes a front planetary 3100, a rear planetary 3200, a C1 clutch 3301, a C2 clutch 3302, a C3 clutch 3303, a C4 clutch 3304, a B1 brake 3311, a B2 brake 3312, and a one-way clutch (F). 3320.

  The front planetary 3100 is a double pinion type planetary gear mechanism. Front planetary 3100 includes a first sun gear (S1) 3102, a pair of first pinion gears (P1) 3104, a carrier (CA) 3106, and a ring gear (R) 3108.

  The first pinion gear (P1) 3104 meshes with the first sun gear (S1) 3102 and the first ring gear (R) 3108. The first carrier (CA) 3106 supports the first pinion gear (P1) 3104 so that it can revolve and rotate.

  First sun gear (S1) 3102 is fixed to gear case 3400 so as not to rotate. First carrier (CA) 3106 is coupled to input shaft 3002 of planetary gear unit 3000.

  The rear planetary 3200 is a Ravigneaux type planetary gear mechanism. The rear planetary 3200 includes a second sun gear (S2) 3202, a second pinion gear (P2) 3204, a rear carrier (RCA) 3206, a rear ring gear (RR) 3208, a third sun gear (S3) 3210, a third Pinion gear (P3) 3212.

  Second pinion gear (P2) 3204 meshes with second sun gear (S2) 3202, rear ring gear (RR) 3208, and third pinion gear (P3) 3212. Third pinion gear (P3) 3212 meshes with third sun gear (S3) 3210 in addition to second pinion gear (P2) 3204.

  The rear carrier (RCA) 3206 supports the second pinion gear (P2) 3204 and the third pinion gear (P3) 3212 so that they can revolve and rotate. Rear carrier (RCA) 3206 is coupled to one-way clutch (F) 3320. The rear carrier (RCA) 3206 becomes non-rotatable when driving the first gear (when traveling using the driving force output from the engine 1000). Rear ring gear (RR) 3208 is coupled to output shaft 3004 of planetary gear unit 3000.

  The one-way clutch (F) 3320 is provided in parallel with the B2 brake 3312. That is, the outer race of the one-way clutch (F) 3320 is fixed to the gear case 3400, and the inner race is connected to the rear carrier (RCA) 3206.

  FIG. 3 shows an operation table showing the relationship between each gear position and the operation state of each clutch and each brake. By operating the brakes and the clutches in the combinations shown in the operation table, a forward 1st to 8th gear and a reverse 1st and 2nd gear are formed.

  The main part of the hydraulic circuit 4000 will be described with reference to FIG. The hydraulic circuit 4000 is not limited to the one described below.

  The hydraulic circuit 4000 includes an oil pump 4004, a primary regulator valve 4006, a manual valve 4100, a solenoid modulator valve 4200, an SL1 linear solenoid (hereinafter referred to as SL (1)) 4210, and an SL2 linear solenoid (hereinafter referred to as “the solenoid valve”). SL2 (described as SL (4)) 4220, SL3 linear solenoid (hereinafter referred to as SL (3)) 4230, SL4 linear solenoid (hereinafter referred to as SL (4)) 4240, and SL5 linear solenoid (hereinafter referred to as SL (3)). , SL (5)) 4250, SLT linear solenoid (hereinafter referred to as SLT) 4300, and B2 control valve 4500.

  Oil pump 4004 is connected to the crankshaft of engine 1000. As the crankshaft rotates, the oil pump 4004 is driven to generate hydraulic pressure. The hydraulic pressure generated by the oil pump 4004 is regulated by the primary regulator valve 4006 to generate a line pressure.

  Primary regulator valve 4006 operates using the throttle pressure regulated by SLT 4300 as a pilot pressure. The line pressure is supplied to the manual valve 4100 via the line pressure oil passage 4010.

  Manual valve 4100 includes a drain port 4105. From the drain port 4105, the oil pressure in the D range pressure oil passage 4102 and the R range pressure oil passage 4104 is discharged. When the spool of the manual valve 4100 is in the D position, the line pressure oil passage 4010 and the D range pressure oil passage 4102 are communicated, and hydraulic pressure is supplied to the D range pressure oil passage 4102. At this time, the R range pressure oil passage 4104 and the drain port 4105 are communicated, and the R range pressure of the R range pressure oil passage 4104 is discharged from the drain port 4105.

  When the spool of the manual valve 4100 is in the R position, the line pressure oil passage 4010 and the R range pressure oil passage 4104 are communicated, and the oil pressure is supplied to the R range pressure oil passage 4104. At this time, the D range pressure oil passage 4102 and the drain port 4105 are communicated, and the D range pressure in the D range pressure oil passage 4102 is discharged from the drain port 4105.

  When the spool of the manual valve 4100 is in the N position, both the D range pressure oil passage 4102 and the R range pressure oil passage 4104 are connected to the drain port 4105, and the D range pressure and R of the D range pressure oil passage 4102 are communicated. The R range pressure of the range pressure oil passage 4104 is discharged from the drain port 4105.

  The hydraulic pressure supplied to the D range pressure oil path 4102 is finally supplied to the C1 clutch 3301, the C2 clutch 3302, and the C3 clutch 3303. The hydraulic pressure supplied to the R range pressure oil passage 4104 is finally supplied to the B2 brake 3312.

  The solenoid modulator valve 4200 adjusts the hydraulic pressure (solenoid modulator pressure) supplied to the SLT 4300 to a constant pressure using the line pressure as the original pressure.

  SL (1) 4210 regulates the hydraulic pressure supplied to the C1 clutch 3301. SL (2) 4220 regulates the hydraulic pressure supplied to C2 clutch 3302. SL (3) 4230 regulates the hydraulic pressure supplied to the C3 clutch 3303. SL (4) 4240 regulates the hydraulic pressure supplied to C4 clutch 3304. SL (5) 4250 regulates the hydraulic pressure supplied to the B1 brake 3311.

  The SLT 4300 adjusts the solenoid modulator pressure in accordance with a control signal from the ECU 8000 based on the accelerator opening detected by the accelerator opening sensor 8010, and generates a throttle pressure. The throttle pressure is supplied to the primary regulator valve 4006 via the SLT oil passage 4302. The throttle pressure is used as a pilot pressure for the primary regulator valve 4006.

  SL (1) 4210, SL (2) 4220, SL (3) 4230, SL (4) 4240, SL (5) 4250, and SLT 4300 are controlled by a control signal transmitted from ECU 8000.

  The B2 control valve 4500 selectively supplies hydraulic pressure from one of the D range pressure oil passage 4102 and the R range pressure oil passage 4104 to the B2 brake 3312. A D range pressure oil passage 4102 and an R range pressure oil passage 4104 are connected to the B2 control valve 4500. The B2 control valve 4500 is controlled by the hydraulic pressure supplied from the SLU solenoid valve (not shown) and the biasing force of the spring.

  When the SLU solenoid valve is on, the B2 control valve 4500 is in the state on the left side in FIG. In this case, the B2 brake 3312 is supplied with the hydraulic pressure adjusted from the D range pressure using the hydraulic pressure supplied from the SLU solenoid valve as a pilot pressure.

  When the SLU solenoid valve is off, the B2 control valve 4500 is in the state on the right side in FIG. In this case, the R range pressure is supplied to the B2 brake 3312.

  The ECU 8000 will be further described with reference to FIG. The functions of ECU 8000 described below may be realized by hardware or may be realized by software.

  ECU 8000 includes an accelerator opening detection unit 8100, a rotation speed detection unit 8102, a throttle opening detection unit 8104, an idle determination unit 8106, a target value setting unit 8108, a limiting unit 8110, and a control unit 8112. .

  The accelerator opening detector 8100 detects the accelerator opening based on the signal transmitted from the accelerator opening sensor 8010.

  The rotation speed detection unit 8102 detects the engine rotation speed NE based on the signal transmitted from the engine rotation speed sensor 8020.

  The throttle opening degree detection unit 8104 detects the throttle opening degree based on the signal transmitted from the throttle opening degree sensor 8018.

  As shown in FIG. 6, the idle determination unit 8106 determines that the engine 1000 is not in an idle state when the throttle opening is equal to or greater than the first threshold value TA (1), and the second threshold value TA (2 ) It is determined that the engine 1000 is in an idle state when A region from the first threshold value TA (1) to the second threshold value TA (2) is a hysteresis region.

  Target value setting unit 8108 sets target throttle opening degree TAT according to accelerator opening degree and engine speed NE. More specifically, the target driving force of the vehicle is set on the basis of the accelerator opening, the engine speed NE, the vehicle speed, and the like according to a map determined in advance based on the results of experiments and simulations. The set target driving force is converted into a target engine torque. For example, the driving force is converted into torque using the radius of rear wheel 7000, the gear ratio of differential gear 6000, the current gear ratio of automatic transmission 2000, the torque ratio of torque converter 2100, and the like. In addition, since the method for converting the driving force into the engine torque (engine output torque) may be a known general technique, further detailed description will not be repeated here.

  A throttle opening that realizes the target engine torque converted from the target driving force is set as the target throttle opening TAT. For example, the target throttle opening degree TAT is set according to a map having the target engine torque as a parameter.

  When it is determined that the variation amount of the accelerator opening is equal to or less than a predetermined value and the engine 1000 is not in the idle state, the limiting unit 8110 sets the target throttle opening TAT to the first threshold value TA (1). Limit to above. Limiting unit 8110 determines that target throttle opening degree TAT is equal to second threshold value TA if it is determined that the amount of change in accelerator opening is equal to or less than a predetermined value and engine 1000 is in an idle state. (2) Restrict to be below.

  For example, if the state in which the change rate of the accelerator opening is equal to or less than the threshold value continues for a predetermined time or more, it is determined that the amount of change in the accelerator opening is equal to or less than a predetermined value. If the difference between the maximum value and the minimum value of the accelerator opening within a predetermined time is equal to or less than the threshold value, it may be determined that the amount of change in the accelerator opening is equal to or less than a predetermined value. Good. In addition, the method of determining whether the fluctuation amount of an accelerator opening is below a predetermined value is not restricted to these.

  The control unit 8112 controls the electronic throttle valve 8016 so that the throttle opening becomes the target throttle opening TAT.

A control structure of a program executed by ECU 8000 will be described with reference to FIG.
In step (hereinafter, step is abbreviated as S) 100, ECU 8000 detects the accelerator opening based on the signal transmitted from accelerator opening sensor 8010. In S102, ECU 8000 detects engine speed NE based on the signal transmitted from engine speed sensor 8020.

  In S104, ECU 8000 sets a target engine torque according to the accelerator opening and engine speed NE. In S106, ECU 8000 sets the throttle opening for realizing the target engine torque as target throttle opening TAT.

  In S108, ECU 8000 determines whether or not the amount of change in accelerator opening is equal to or less than a threshold value. That is, it is determined whether or not the accelerator opening is substantially constant. If the amount of change in accelerator opening is equal to or less than the threshold value (YES in S108), the process proceeds to S110. If not (NO in S108), the process proceeds to S140.

  In S110, ECU 8000 detects the throttle opening based on the signal transmitted from throttle opening sensor 8018. In S112, ECU 8000 determines whether engine 1000 is in an idle state or not. If the engine is in an idle state (YES in S112), that is, if the throttle opening is equal to or smaller than second threshold value TA (2), the process proceeds to S120. If the engine is not in an idle state (NO in S112), that is, if the throttle opening is equal to or greater than first threshold value TA (1), the process proceeds to S130.

  In S120, ECU 8000 determines whether target throttle opening degree TAT is equal to or smaller than second threshold value TA (2). If target throttle opening degree TAT is equal to or smaller than second threshold value TA (2) (YES in S120), the process proceeds to S140. If target throttle opening degree TAT is larger than second threshold value TA (2) (NO in S120), the process proceeds to S122.

  In S122, ECU 8000 sets second threshold value TA (2) to target throttle opening degree TAT. That is, the target throttle opening degree TAT is limited to be equal to or smaller than the second threshold value TA (2).

  In S130, ECU 8000 determines whether target throttle opening degree TAT is equal to or larger than first threshold value TA (1). If target throttle opening degree TAT is equal to or larger than first threshold value TA (1) (YES in S130), the process proceeds to S140. If target throttle opening degree TAT is smaller than first threshold value TA (1) (NO in S130), the process proceeds to S132.

  In S132, ECU 8000 sets first threshold value TA (1) to target throttle opening degree TAT. That is, the target throttle opening degree TAT is limited to be equal to or greater than the first threshold value TA (1).

  In S140, ECU 8000 controls electronic throttle valve 8016 so that the throttle opening becomes target throttle opening TAT.

  The operation of the control device according to the present embodiment based on the above-described structure and flowchart will be described.

  While the vehicle is traveling, the accelerator opening is detected based on the signal transmitted from the accelerator opening sensor 8010 (S100). Based on the signal transmitted from engine speed sensor 8020, engine speed NE is detected (S102).

  Further, the target engine torque is set according to the accelerator opening and the engine speed NE (S104). A throttle opening for realizing the target engine torque is set as the target throttle opening TAT (S106).

  If the fluctuation amount of the accelerator opening is larger than the threshold value (NO in S108), that is, if the accelerator opening is changed, electronic throttle valve 8016 is controlled so that the throttle opening becomes target throttle opening TAT. (S140). Thus, engine 1000 can be controlled in accordance with the driver's intention.

  If the amount of change in accelerator opening is equal to or less than the threshold value (YES in S108), that is, if the accelerator opening is substantially constant, the throttle opening is determined based on the signal transmitted from throttle opening sensor 8018. It is detected (S110), and it is determined whether the engine 1000 is in an idle state (S112).

  If engine 1000 is in an idle state (YES in S112), that is, if throttle opening is equal to or smaller than second threshold value TA (2), target throttle opening degree TAT is equal to second threshold value TA (2). It is determined whether or not the following is true (S120).

  If target throttle opening degree TAT is equal to or smaller than second threshold value TA (2) (YES in S120), electronic throttle valve 8016 is controlled so that the throttle opening degree becomes target throttle opening degree TAT (S140). .

  If target throttle opening degree TAT is larger than second threshold value TA (2) (NO in S120), second threshold value TA (2) is set to target throttle opening degree TAT (S122), and throttle opening degree The electronic throttle valve 8016 is controlled so that becomes the target throttle opening degree TAT (S140).

  Thus, when the accelerator opening is substantially constant and it is determined that the engine 1000 is in the idle state, the throttle opening is prevented from becoming larger than the second threshold TA (2). Can do. Therefore, the operating state of engine 1000 can be maintained in an idle state.

  On the other hand, if the engine is not in the idle state (NO in S112), that is, if the throttle opening is equal to or greater than first threshold value TA (1), target throttle opening degree TAT is equal to or greater than first threshold value TA (1). It is determined whether or not (S130).

  If target throttle opening degree TAT is equal to or greater than first threshold value TA (1) (YES in S130), electronic throttle valve 8016 is controlled so that the throttle opening degree becomes target throttle opening degree TAT (S140). .

  If target throttle opening degree TAT is smaller than first threshold value TA (1) (NO in S130), first threshold value TA (1) is set to target throttle opening degree TAT (S132), and throttle opening degree The electronic throttle valve 8016 is controlled so that becomes the target throttle opening degree TAT (S140).

  Thus, when it is determined that the accelerator opening is substantially constant and the engine 1000 is not in the idle state, the throttle opening is prevented from becoming smaller than the first threshold value TA (1). it can. Therefore, the operating state of engine 1000 can be maintained in a state other than the idle state.

  As a result, when the accelerator opening is substantially constant, the throttle opening changes from the region above the first threshold TA (1) to the region below the second threshold TA (2), or vice versa. In addition, it is possible to prevent the throttle opening from changing from the region below the second threshold TA (2) to the region above the first threshold TA (1). Therefore, it is possible to stabilize the determination result of whether or not the engine is in the idle state.

  As described above, according to the control device according to the present embodiment, when it is determined that the accelerator opening is substantially constant and the engine is not in the idle state, the throttle opening is the first threshold. It is limited to the value TA (1) or more. When it is determined that the accelerator opening is substantially constant and the engine is in an idle state, the throttle opening is limited to the second threshold value TA (2) or less. As a result, when the accelerator opening is substantially constant, the throttle opening changes from the region above the first threshold TA (1) to the region below the second threshold TA (2), or vice versa. In addition, it is possible to prevent the throttle opening from changing from the region below the second threshold TA (2) to the region above the first threshold TA (1). Therefore, it is possible to stabilize the determination result of whether or not the engine is in the idle state.

<Second Embodiment>
Hereinafter, a second embodiment of the present invention will be described. This embodiment is different from the first embodiment described above in that the target engine torque is limited instead of the target throttle opening degree TAT. Other configurations are the same as those in the first embodiment. Therefore, detailed description thereof will not be repeated here.

  Referring to FIG. 8, limiting unit 8114 of ECU 8000 in the present embodiment provides a target when it is determined that the amount of change in accelerator opening is equal to or less than a predetermined value and engine 1000 is not in an idle state. The engine torque is limited to be equal to or higher than a third threshold value TE (3) indicated by a one-dot chain line in FIG. The third threshold value TE (3) is the engine torque when the throttle opening is the first threshold value TA (1).

  Therefore, when the engine torque is equal to or greater than the third threshold value TE (3), the throttle opening is equal to or greater than the first threshold value TA (1). Therefore, it can be determined that engine 1000 is not in an idle state.

  Limiting unit 8114 indicates that the target engine torque is indicated by a two-dot chain line in FIG. 9 when it is determined that the fluctuation amount of the accelerator opening is equal to or less than a predetermined value and engine 1000 is in an idle state. It limits so that it may become below 4th threshold value TE (4). The fourth threshold value TE (4) is the engine torque when the throttle opening is the second threshold value TA (2).

  Therefore, when the engine torque is equal to or smaller than the fourth threshold value TE (4), the throttle opening is equal to or smaller than the second threshold value TA (2). Therefore, it can be determined that engine 1000 is in an idle state.

  A control structure of a program executed by ECU 8000 will be described with reference to FIG. Note that the same step numbers are assigned to the same processes as those in the first embodiment. Therefore, detailed description thereof will not be repeated here.

  In S220, ECU 8000 determines whether or not the target engine torque is equal to or smaller than fourth threshold value TE (4). If target engine torque is equal to or smaller than fourth threshold value TE (4) (YES in S220), the process proceeds to S106. If target engine torque is greater than fourth threshold value TE (4) (NO in S220), the process proceeds to S222.

  In S222, ECU 8000 sets fourth threshold value TE (4) as the target engine torque. That is, the target engine torque is limited to be equal to or less than the fourth threshold value TE (4).

  In S230, ECU 8000 determines whether target engine torque is equal to or greater than third threshold value TE (3). If target engine torque is equal to or greater than third threshold value TE (3) (YES in S230), the process proceeds to S106. If target engine torque is smaller than third threshold value TE (3) (NO in S230), the process proceeds to S232.

  In S232, ECU 8000 sets third threshold value TE (3) as the target engine torque. That is, the target engine torque is limited to be equal to or greater than the third threshold value TE (3).

  In this manner, as shown by the solid line in FIG. 11, when the accelerator opening is substantially constant and it is determined that the engine 1000 is in the idle state, the engine torque is the fourth threshold value. It can be prevented from becoming larger than TE (4). Therefore, it is possible to prevent the throttle opening from becoming larger than the second threshold value TA (2). As a result, the operating state of engine 1000 can be maintained in an idle state.

  On the other hand, when it is determined that the accelerator opening is substantially constant and the engine 1000 is not in the idle state, the engine torque is determined from the third threshold value TE (3) as shown by the solid line in FIG. It can be made smaller. Therefore, it is possible to prevent the throttle opening from becoming smaller than the first threshold value TA (1). As a result, the operating state of engine 1000 can be maintained in a state other than the idle state.

  Therefore, when the accelerator opening is substantially constant, the throttle opening changes from the region above the first threshold TA (1) to the region below the second threshold TA (2), or conversely It is possible to prevent the throttle opening from changing from the region below the second threshold TA (2) to the region above the first threshold TA (1). Therefore, it is possible to stabilize the determination result of whether or not the engine is in the idle state.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

It is a schematic block diagram which shows the power train of a vehicle. It is a skeleton figure which shows the planetary gear unit of an automatic transmission. It is a figure which shows the operation | movement table | surface of an automatic transmission. It is a figure which shows the hydraulic circuit of an automatic transmission. It is a functional block diagram of ECU in the 1st Embodiment of this invention. It is a figure which shows 1st threshold value TA (1) and 2nd threshold value TA (2) used in order to determine whether an engine is an idle state. It is a flowchart which shows the control structure of the program which ECU runs in the 1st Embodiment of this invention. It is a functional block diagram of ECU in the 2nd Embodiment of this invention. It is a figure which shows 3rd threshold value TE (3) and 4th threshold value TA (4). It is a flowchart which shows the control structure of the program which ECU runs in the 2nd Embodiment of this invention. It is a figure which shows an engine torque in case the accelerator opening is substantially constant and it determines with an engine being an idle state. It is a figure which shows an engine torque in case it is determined with the accelerator opening being substantially constant and an engine not being in an idle state.

Explanation of symbols

  1000 engine, 2000 automatic transmission, 2100 torque converter, 3000 planetary gear unit, 4000 hydraulic circuit, 6000 differential gear, 7000 rear wheel, 8000 ECU, 8002 ROM, 8004 shift lever, 8006 position switch, 8008 accelerator pedal, 8010 accelerator opening sensor , 8012 Air flow meter, 8016 Electronic throttle valve, 8018 Throttle opening sensor, 8020 Engine speed sensor, 8022 Input shaft speed sensor, 8024 Output shaft speed sensor, 8026 Oil temperature sensor, 8028 Water temperature sensor, 8100 Accelerator opening detection , 8102 Rotation speed detection unit, 8104 Throttle opening detection unit, 8106 Idle determination unit, 8 08 target value setting unit, 8110,8114 limiting part 8112 control unit.

Claims (5)

Means for detecting the accelerator opening;
Means for detecting the output shaft speed of the engine;
Means for setting a target value of the value indicating the operating state of the engine according to the accelerator opening and the output shaft rotational speed of the engine;
Means for controlling the engine such that a value indicating an operating state of the engine becomes the target value;
Means for detecting a value indicative of the operating state of the engine;
First determination means for determining that the engine is not in an idle state when a value indicating an operating state of the engine is in a first region;
Second determination means for determining that the engine is in an idle state when a value indicating the operating state of the engine is in a second region;
Limiting means for limiting the target value to be in one of the first region and the second region when the amount of change in the accelerator opening is equal to or less than a predetermined value. An engine control device comprising: The limiting means is
Means for limiting the target value to be in the first region when it is determined that the amount of change in the accelerator opening is equal to or less than a predetermined value and the engine is not in an idle state; ,
Means for limiting the target value to be in the second region when the fluctuation amount of the accelerator opening is equal to or less than a predetermined value and the engine is determined to be in an idle state. The engine control device according to claim 1, comprising: The engine is provided with a throttle valve,
The engine control device according to claim 1, wherein the value indicating the operating state of the engine is a throttle opening.   The engine control device according to claim 1, wherein the value indicating the operating state of the engine is an output torque of the engine. The first region is a region equal to or greater than a first threshold;
The engine control apparatus according to claim 3 or 4, wherein the second region is a region equal to or smaller than a second threshold value that is smaller than the first threshold value.

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