JP2020045801A - Vehicle control device - Google Patents

Abstract

To provide a vehicle control device which improves accuracy of determining driving and driven states of a vehicle while the same is in coasting operation.SOLUTION: A vehicle control device: determines whether a vehicle 10 is in coasting operation with a fuel-cut switch turned on or off before being shifted to accelerated operation (Step S10); sets a driven state threshold value when the vehicle is in the coasting operation before being shifted to the accelerated operation with the fuel-cut switch turned off higher than the same when the vehicle is in the coasting operation before being shifted to the accelerated operation with the fuel-cut switch turned on (Steps S20 and S50); and determines whether or not engine torque Tereal after the vehicle is shifted to the accelerated operation is equal to or less than the driven state threshold values set for the case with the fuel-cut switches turned on or off (Steps S40 and S70). Through these determinations, the vehicle control device can improve accuracy of determining whether the vehicle 10 is in a driving state or a driven state.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a vehicle control device for shock reduction control for gently reducing backlash of a power transmission member when switching from coasting to acceleration running.

  The state of the vehicle includes a driving state in which the driving wheels are driven by the torque output from the engine, and a driven state in which the engine is driven by the torque input from the driving wheels. Then, there is known a control device for a vehicle that performs a shock reduction control for gradually reducing the backlash when changing from the driven state to the driven state. For example, a vehicle control device described in Patent Literature 1 is that.

JP-A-2004-324584

  By the way, there is a case where it is desired to use the deceleration control with the fuel cut and the deceleration control without the fuel cut properly in the coasting. In the vehicle control device described in Patent Literature 1, the engine is in a driving state when the engine is operating, and is in a driven state when the engine is not operating such as during fuel cut. For this reason, the deceleration control without fuel cut in the coasting operation is erroneously determined as the driving state despite the driven state because the engine is operating, and the shock reduction control when switching from the coasting to the acceleration traveling is performed. May not be implemented. Therefore, in order to improve the accuracy of determining the driving state and the driven state of the vehicle during coasting, it is conceivable to determine whether the vehicle is in the driving state or the driven state based on the magnitude of the engine torque. . However, even in the driven state during the same coasting, the engine torque value is significantly different between the deceleration control with fuel cut and the deceleration control without fuel cut, so that the drive state and the driven state are not correctly determined. There is.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a vehicle control device that improves the accuracy of determining the driving state and the driven state of a vehicle during coasting. is there.

  The gist of the present invention is a control device for a vehicle that selectively performs one of first deceleration control with fuel cut and second deceleration control without fuel cut as deceleration control in coasting, The fuel cut determination unit determines whether the coasting before switching to the acceleration traveling is the first deceleration control or the second deceleration control, and the fuel cut determination unit determines that the inertia traveling is the first deceleration control. Then, a predetermined first determination value is set as a driven state threshold value, and when the fuel cut determination unit determines that the second deceleration control has been performed, a predetermined second determination value higher than the first determination value is set. A threshold setting unit that sets the driven state threshold value; and a threshold setting unit that sets the engine torque after switching to the acceleration traveling by the threshold setting unit. In further comprising not a driven state determining unit determines whether there are less moving-state threshold, the.

  According to the vehicle control device of the present invention, the fuel cut determination unit that determines whether the coasting before switching to the acceleration traveling is the first deceleration control or the second deceleration control, and the first deceleration control When it is determined by the fuel cut determination section that the above is the case, a predetermined first determination value is set as a driven state threshold value, and when it is determined by the fuel cut determination section that it is the second deceleration control, the second determination is performed. A threshold setting unit that sets a predetermined second determination value higher than one determination value as the driven state threshold; and the driven state threshold that is set by the threshold setting unit for an engine torque after switching to the acceleration traveling. And a driven state determination unit that determines whether or not the following conditions are satisfied. The output state of the engine changes depending on the presence or absence of the fuel cut. However, as described above, the driven state threshold value in the second deceleration control without the fuel cut is changed to the driven state threshold value in the first deceleration control with the fuel cut. Set higher than that. Thus, by determining whether or not the engine torque is equal to or less than the driven state threshold, the accuracy of determining whether the vehicle is in the driven state or the driven state is improved.

FIG. 1 is a diagram illustrating a schematic configuration of a vehicle to which the present invention is applied, and is a functional block diagram illustrating a control function of an electronic control device for performing various controls in the vehicle and a main part of a control system. 2 is an example of a flowchart illustrating a control operation of the electronic control device illustrated in FIG. 1.

  In one embodiment of the present invention, when the driven state determination unit determines that the engine torque is equal to or less than the driven state threshold value, a shock reduction control that gradually reduces backlash when switching to the accelerated traveling is performed. An acceleration control unit that does not execute the shock reduction control when switching to the acceleration traveling when the driven state determination unit determines that the engine torque exceeds the driven state threshold value. By determining whether or not the engine torque is equal to or less than the driven state threshold value, the accuracy of determining whether the vehicle is in the driven state or the driven state is improved, and based on the result of the improved accuracy. Thus, when switching from the inertial running to the acceleration running, the shock reduction control is performed according to the actual vehicle state.

  In one embodiment of the present invention, when the driven state determination unit determines that the engine torque is equal to or less than the driven state threshold value, a shock reduction control that gradually reduces backlash when switching to the accelerated traveling is performed. An acceleration control unit that does not perform the shock reduction control when switching to the accelerated traveling when the driven state determination unit determines that the engine torque exceeds the driven state threshold value; When it is determined by the fuel cut determination unit that the deceleration control is performed, when the driven state determination unit determines that the engine torque exceeds the driven state threshold, the torque converter determines the engine torque based on the engine rotation speed. A differential rotation determination unit that determines whether the differential rotation speed obtained by subtracting the turbine rotation speed is equal to or less than a predetermined determination rotation speed. When the differential rotation determining unit determines that the differential rotation speed is equal to or less than the determination rotation speed, the acceleration control unit performs the shock reduction control, and the differential rotation speed exceeds the determination rotation speed. The acceleration control unit does not execute the shock reduction control if the differential rotation determination unit determines that the shock reduction is performed. As described above, even if the coasting before switching to the acceleration traveling is the second deceleration control and the engine torque after switching to the acceleration traveling is equal to or less than the driven state threshold value, the differential rotation speed is equal to the predetermined determination rotation speed. Is exceeded, it is determined that the vehicle is in the driving state, and the shock reduction control is not performed. For example, even when the deceleration flex control in which the lock-up clutch of the torque converter is half-engaged during coasting has been performed, if the differential rotation speed exceeds a predetermined determination rotation speed, the vehicle Is accurately determined to be in the driving state. If the actual vehicle state is the driving state based on the result determined with high accuracy, the shock reduction control is not performed and acceleration can be performed without delay.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a diagram illustrating a schematic configuration of a vehicle 10 to which the present invention is applied, and a functional block diagram illustrating a control function of an electronic control device 80 for various controls in the vehicle 10 and a main part of a control system. It is.

  First, a schematic configuration of the vehicle 10 will be described with reference to FIG. The vehicle 10 includes an engine 12, a power transmission device 30, an axle 34, and drive wheels 36. The power transmission device 30 includes the torque converter 14, the automatic transmission 18, the reduction gear mechanism 24, and the differential gear 26 in a case 32 that is a non-rotating member. In the power transmission device 30, the power output from the engine 12 (the torque and the force also have the same meaning unless otherwise specified) are sequentially transmitted to the torque converter 14, the automatic transmission 18, the reduction gear mechanism 24, and the differential gear 26. Go.

  The engine 12 is a driving force source of the vehicle 10, and is a known internal combustion engine such as a gasoline engine or a diesel engine. The engine 12 controls the engine torque Te (Nm) by controlling operating states such as an intake air amount, a fuel supply amount, and an ignition timing by an electronic control device 80 described later.

  The torque converter 14 includes a pump impeller 14p connected to a crankshaft of the engine 12, and a turbine impeller 14t connected to an input shaft 20 of the automatic transmission 18, and performs fluid power transmission for transmitting power via fluid. Device. A lock-up clutch LU is provided between the pump wheel 14p and the turbine wheel 14t. The connection / disconnection state of the lock-up clutch LU is controlled by a hydraulic control command signal Sat output from the electronic control unit 80 as described later. The lock-up clutch LU may be completely engaged or completely released, or may be semi-engaged in which the pump impeller 14p and the turbine impeller 14t slip. An oil pump 16 is connected to the pump impeller 14p. The oil pump 16 is rotationally driven by the engine 12 to pump hydraulic oil to a hydraulic control circuit 50 described below.

  The automatic transmission 18 is constituted by a speed change mechanism such as a planetary gear type stepped transmission, a constantly meshing parallel shaft type stepped transmission, or a belt type continuously variable transmission. The automatic transmission 18 changes the speed of rotation of the input shaft 20 and outputs the rotation to the output gear 22.

  The reduction gear mechanism 24 reduces the rotation of the power transmitted from the output gear 22 and transmits the power to a differential gear 26, and the differential gear 26 transmits the transmitted power to a drive wheel 36 via an axle 34.

  When the vehicle 10 is switched from a driven state in which the engine 12 is driven by the torque input from the drive wheels 36 to a drive state in which the drive wheels 36 are driven by the torque output from the engine 12, the differential gear 26 Power transmission is temporarily interrupted due to backlash existing in the like. Thereafter, when the transmission of power is resumed, the kinetic energy accumulated by the backlash is rapidly transmitted, and a strong shock (shock) is generated in the vehicle 10. The backlash is a gap (play) between a contact surface at a gear or a spline fitting portion formed in a rotational direction in a power transmission member. As described above, there are two states of the vehicle 10, a driving state and a driven state. When the transmission of power is temporarily interrupted due to the backlash, the engine 12 is not driven by the torque input from the drive wheel 36 and the drive wheel 36 is driven by the torque output from the engine 12. Not even. Therefore, the state in which the transmission of power is temporarily interrupted is strictly a non-driving state. However, in the present embodiment, since it is intended to reduce the shock at the time of switching to the driving state, no particular distinction is made. In this case, the driven state is set for convenience.

  The electronic control unit 80 is also called an ECU, and is configured to include a so-called microcomputer having a CPU, a RAM, a ROM, and an input / output interface, and the like. By performing signal processing according to the stored program, various devices of the vehicle 10 are controlled. Note that the electronic control unit 80 corresponds to the “control unit” in the present invention.

  When the vehicle 10 is switched from the driven state to the driven state, the electronic control unit 80 can perform the shock reduction control for reducing the shock generated by the backlash described above. In the shock reduction control, when switching from the driven state to the driving state, a small torque required to reduce the backlash is output for a short time to perform the backlash reduction. In the backlash filling, the electronic control unit 80 calculates the required torque of the engine 12 for filling the backlash without generating a shock, and the control time for controlling the torque of the engine 12 based on the required torque. The output is adjusted based on the calculated required torque and control time. After the backlash is filled, the backlash is set to a play-free state in the rotation direction of the power transmission member when the backlash is in a driving state, and then the engine 12 is controlled based on the accelerator opening θacc (%) representing the operation amount of the accelerator pedal. The output is adjusted.

  Here, coasting and acceleration traveling will be described. The inertial running is running with the accelerator pedal turned off (the accelerator pedal is not depressed). The deceleration control in coasting includes first deceleration control with fuel cut and second deceleration control without fuel cut. Fuel cut is to stop supplying fuel to the engine 12. Since the first deceleration control is control involving fuel cut (hereinafter referred to as fuel cut ON), no power is output from the engine 12. As the first deceleration control, for example, during deceleration traveling in which the accelerator pedal is not depressed, the lock-up clutch LU is completely released or half-engaged to suppress the mechanical connection between the pump impeller 14p and the turbine impeller 14t. There is control. The second deceleration control is control that does not involve fuel cut (hereinafter, referred to as fuel cut OFF), and power is output from the engine 12. As the second deceleration control, for example, during deceleration traveling where the accelerator pedal is not depressed, the lock-up clutch LU is not completely engaged and the pump impeller 14p and the turbine impeller 14t are locked at a predetermined differential rotation speed. There is a deceleration flex control in which the LU is half-engaged so as to slip. The accelerated traveling is a traveling in which the accelerator pedal is turned ON (a state in which the accelerator pedal is depressed), and is a state in which the accelerator pedal is depressed by the driver to request the vehicle 10 to accelerate.

  Hereafter, the control function of the electronic control unit 80 and various parts of the control system for various controls in the vehicle 10 will be described with reference to FIG. The electronic control unit 80 includes the engine rotation speed Ne (rpm) detected by the engine rotation speed sensor 52, the input shaft rotation speed sensor 54, the accelerator opening sensor 56, and the throttle valve opening sensor 58, and the turbine wheel 14t. The input shaft rotation speed Ni (rpm), which is also the rotation speed (i.e., the turbine rotation speed Nt (rpm)), the accelerator opening θacc (%) that represents the operation amount of the accelerator pedal, and the throttle valve that is the opening of the electronic throttle valve The opening degree θth (%) is input. From the electronic control unit 80, the engine control command signal Se is output to the engine 12, the hydraulic control command signal Sat is output to the hydraulic control circuit 50, and the torque control 14 is controlled via the operation control of the engine 12 and the hydraulic control circuit 50. The connection / disconnection control of the provided lock-up clutch LU and the speed change control of the speed change mechanism provided in the automatic transmission 18 are performed.

  The electronic control unit 80 functionally controls the fuel cut determination unit 80a, the threshold setting unit 80b, the first engine torque determination unit 80c, the second engine torque determination unit 80d, the differential rotation determination unit 80e, and the acceleration control unit 80f. Prepare. Note that the second engine torque determination unit 80d corresponds to a "driven state determination unit" in the present invention.

  The fuel cut determination unit 80a determines whether the coasting before switching is the first deceleration control when the vehicle is switched to the acceleration traveling with the accelerator pedal ON during the coasting with the accelerator pedal OFF (that is, the fuel is deactivated). It is determined whether or not the cut is ON. Switching from the accelerator pedal OFF to the accelerator pedal ON is determined, for example, based on the accelerator opening θacc. Whether or not the coasting before switching is the first deceleration control is determined based on, for example, flag information indicating whether the fuel cut is ON or the fuel cut is OFF during the coasting.

  When the fuel cut determination unit 80a determines that the coasting is the first deceleration control, the threshold setting unit 80b sets a predetermined FCON drive determination value TON1 (Nm) as a drive state threshold, and sets a predetermined FCON load control value. The drive determination value TON2 (Nm) is set as the driven state threshold value. When the fuel cut determination unit 80a determines that the coasting is not the first deceleration control (that is, the coasting is the second deceleration control), the threshold setting unit 80b determines the predetermined FCOFF drive determination value TOFF1 ( Nm) is set as the drive state threshold, and a predetermined FCOFF driven determination value TOFF2 (Nm) is set as the drive state threshold. The values of the FCON drive determination value TON1, the FCON drive determination value TON2, the FCOFF drive determination value TOFF1, and the FCOFF drive determination value TOFF2 will be described later. The FCON driven determination value TON2 corresponds to the “predetermined first determination value” in the present invention, and the FOFF driven determination value TOFF2 corresponds to the “predetermined second determination value” in the present invention.

  When the driving state threshold value and the driven state threshold value are set by the threshold value setting unit 80b, the first engine torque determination unit 80c drives the engine torque Tereal (Nm) after the accelerator pedal is turned ON after switching to acceleration running. It is determined whether or not the time that is equal to or greater than the state threshold has exceeded a predetermined drive determination time TDRVACCON (ms). The engine torque Tereal can be derived as an estimated value (calculated value) from a map previously experimentally obtained and set using the engine speed Ne and the throttle valve opening θth as parameters, for example.

  The drive determination value TON1 for FCON and the drive determination time TDRVACCON are set such that after the accelerator pedal is turned on during the inertia traveling of the first deceleration control, the engine torque Tereal continues to be the drive determination value TON1 for FCON after the drive determination time TDRVACCON. In this case, the value is set experimentally in advance as a value that is set to a state in which there is no play in the rotation direction of the power transmission member when the backlash is in the driving state. The FCOFF drive determination value TOFF1 and the drive determination time TDRVACCON are determined by setting the accelerator pedal ON during the inertia running of the second deceleration control and continuing the engine torque Tereal during the drive determination time TDRVACCON during the FCOFF drive determination value TOFF1. In this case, the value is set experimentally in advance as a value that is set to a state in which there is no play in the rotation direction of the power transmission member when the backlash is in the driving state. The FCOFF drive determination value TOFF1 is higher than the FCON drive determination value TON1. Even in the driven state in the same inertia running, in the first deceleration control in which the fuel cut is ON, no power is output from the engine 12, the engine torque Tereal is zero, and in the second deceleration control in which the fuel cut is OFF, Power is being output from the engine 12, and the engine torque Tereal has a positive value. Accordingly, the engine torque Tereal for making the backlash playless after the accelerator pedal is turned on is smaller when the accelerator pedal is turned on in the coasting of the second deceleration control than in the case of the coasting of the first deceleration control. This is because it becomes higher than when the pedal is turned ON.

  If the first engine torque determination unit 80c determines that the time during which the engine torque Tereal is equal to or greater than the drive state threshold after the accelerator pedal is turned on does not exceed the drive determination time TDRVACCON, the second engine torque determination unit At 80d, it is determined whether or not the time during which the engine torque Tereal is equal to or less than the driven state threshold value after the accelerator pedal is turned on after the switching to the acceleration traveling has exceeded a predetermined driven determination time TDRVACCOFF (ms). The first engine torque determination unit 80c determines in this manner, for example, when the engine torque Tereal is less than the drive state threshold continuously during the drive determination time TDRVACCON, during the drive determination time TDRVACCON. The state where the engine torque Tereal is equal to or greater than the drive state threshold temporarily but is equal to or greater than the drive state threshold is, for example, the case where the engine torque is equal to or less than the drive determination time TDRVACCON.

  The driven determination value TON2 for FCON and the driven determination time TDRVACCOFF are maintained during the period of the driven determination time TDRVACCOFF after the accelerator pedal is turned on during the coasting of the first deceleration control, and the engine torque Tereal continues to be reduced for the FCON. Even when the drive determination value TON2 is set, it is experimentally determined in advance as a value that is not set to a play-free state in the rotation direction of the power transmission member when the backlash is in the drive state. The driven determination value TOFF2 for FCOFF and the driven determination time TDRVACCOFF are maintained during the driven determination time TDRVACCOFF after the accelerator pedal is turned on during the coasting of the second deceleration control, and the engine torque Tereal continues to be reduced for the FCOFF. Even with the drive determination value TOFF2, it is experimentally obtained and set in advance as a value that does not cause a play in the rotational direction of the power transmission member when the backlash is in the drive state. The FCOFF driven determination value TOFF2 is higher than the FCON driven determination value TON2. This is the same as the reason why the FCOFF drive determination value TOFF1 is higher than the FCON drive determination value TON1 described above.

  When the first engine torque determination unit 80c determines that the time during which the engine torque Tereal is equal to or greater than the drive state threshold has exceeded the drive determination time TDRVACCON after the accelerator pedal is turned on, the acceleration control unit 80f switches the vehicle 10 to the drive state. If so, the shock reduction control is not performed. This is because if it is determined in this way, it is considered that the backlash is already in a state without play and the vehicle 10 is in a driving state. Further, since the accelerator opening degree θacc is large, that is, the accelerator pedal is strongly depressed by the driver, the driver is required to accelerate the vehicle 10 more quickly than performing the shock reduction control to reduce the backlash gently. Is thought to want.

  The second engine determines that the inertia running is the first deceleration control by the fuel cut determination unit 80a and that the time during which the engine torque Tereal is equal to or less than the driven state threshold after the accelerator pedal is turned on exceeds the driven determination time TDRVACCOFF. When determined by the torque determination unit 80d, the acceleration control unit 80f performs the shock reduction control on the assumption that the vehicle 10 is in the driven state. This is because if it is determined in this way, the backlash is not yet in a state where there is no play, and it is considered that the driven state of the vehicle 10 is maintained. Further, since the accelerator opening θacc by the driver is small, that is, the accelerator pedal is weakly depressed by the driver, the driver can easily feel the shock generated by the backlash, so that the shock reduction control is performed. Is desirable.

  It cannot be said that the time during which the inertia running is the first deceleration control by the fuel cut determination unit 80a and the engine torque Tereal is equal to or less than the driven state threshold after the accelerator pedal is turned on has exceeded the driven determination time TDRVACCOFF. When determined by the second engine torque determination unit 80d, the acceleration control unit 80f does not execute the shock reduction control. In this manner, the second engine torque determination unit 80d determines, for example, when the engine torque Tereal continuously exceeds the driven state threshold during the period of the driven determination time TDRVACCOFF, the driven determination time TDRVACCOFF. In the period, the state where the engine torque Tereal is temporarily equal to or lower than the driven state threshold value is temporarily, but the state where the engine torque is equal to or lower than the driven state threshold value is a case where the engine torque Tereal is equal to or less than the driven determination time TDRVACCOFF. Although the vehicle 10 may be in a non-driving state, the backlash backlash has already been somewhat reduced because there is a period in which the engine torque Tereal exceeds the driven state threshold value. This is because it is considered that the occurrence of the shock has been reduced without performing.

  When the fuel cut determination unit 80a determines that the inertia running is the second deceleration control, and the second engine determines that the time during which the engine torque Tereal is equal to or less than the driven state threshold value after the accelerator pedal is turned on exceeds the driven determination time TDRVACCOFF. When determined by the torque determination unit 80d, the differential rotation determination unit 80e determines that the differential rotation speed NSLP (rpm) obtained by subtracting the turbine rotation speed Nt from the engine rotation speed Ne is a predetermined determination rotation speed. rpm) or not.

  When the differential rotation speed NSLP is equal to or less than the differential rotation speed determination value NSLP_thr, the differential rotation speed determination value NSLP_thr is a determination value that does not cause a play in the rotation direction of the power transmission member when the backlash is driven. , For example, zero or a value slightly larger than zero, which is previously determined experimentally or by design and set. For example, when the deceleration / deceleration flex control is performed as the second deceleration control, the mechanical connection between the engine 12 and the drive wheels 36 is suppressed in the torque converter 14. However, the connection between the engine 12 and the drive wheels 36 via the fluid of the torque converter 14 and the connection in a state in which the lock-up clutch LU slips (half-engagement) are performed. The turbine rotation speed Nt corresponds to the rotation speed of the drive wheel 36. Therefore, when the engine rotation speed Ne is equal to or less than the value obtained by adding the above-described difference rotation speed determination value NSLP_thr to the turbine rotation speed Nt, the vehicle 10 is driven by the torque input from the drive wheels 36 to drive the engine 12. It is considered that this is the case where the driving state is not set to the state where the backlash is not loose. On the other hand, when the engine rotation speed Ne exceeds the value obtained by adding the above-described difference rotation speed determination value NSLP_thr to the turbine rotation speed Nt, the drive wheels 36 of the vehicle 10 are driven by the torque output from the engine 12. This is considered to be the case where the driving state is such that the backlash is in a state without play.

  It cannot be said that the time during which the inertia running is the second deceleration control by the fuel cut determination unit 80a and the engine torque Tereal is equal to or less than the driven state threshold after the accelerator pedal is turned on has exceeded the driven determination time TDRVACCOFF. When determined by the second engine torque determination unit 80d, the acceleration control unit 80f does not execute the shock reduction control. Although the vehicle 10 may be in a non-driving state, the backlash backlash has already been somewhat reduced because there is a period in which the engine torque Tereal exceeds the driven state threshold value. This is because it is considered that the occurrence of the shock has been reduced without performing.

  If the difference rotation speed determination unit 80e determines that the difference rotation speed NSLP is equal to or less than the difference rotation speed determination value NSLP_thr, the acceleration control unit 80f performs shock reduction control assuming that the vehicle 10 is in a driven state. If the determination is made in this manner, the vehicle 10 is considered to be in the driven state, as described above, and therefore, it is necessary to perform the shock reduction control for performing the backlash filling.

  If the difference rotation speed determination unit 80e determines that the difference rotation speed NSLP exceeds the difference rotation speed determination value NSLP_thr, the acceleration control unit 80f does not perform the shock reduction control because the vehicle 10 is in the driving state. If the determination is made in this manner, the vehicle 10 is considered to be in the driving state as described above, and therefore, it is not necessary to perform the shock reduction control for executing the backlash filling.

  FIG. 2 is an example of a flowchart illustrating the control operation of the electronic control unit 80 shown in FIG. In the flowchart of FIG. 2, the start is executed when the vehicle 10 is switched from coasting to acceleration traveling. For example, the operation is started based on the fact that the accelerator opening θacc corresponding to the accelerator pedal ON has been detected during the coasting operation in which the accelerator pedal is OFF.

  First, in step S10 corresponding to the fuel cut determination unit 80a, when the vehicle is switched to the acceleration traveling in which the accelerator pedal is ON while the coasting in which the accelerator pedal is OFF, the coasting before the switching is performed by the first deceleration control. It is determined whether or not there is (that is, whether or not the fuel cut is ON). If the determination in step S10 is affirmative, that is, in the case of the first deceleration control, step S20 is executed. If the determination in step S10 is negative, that is, in the case of the second deceleration control, step S50 is executed.

  In step S20 corresponding to the threshold setting unit 80b, the FCON drive determination value TON1 is set as the drive state threshold, and the FCON driven determination value TON2 is set as the driven state threshold. Then, step S30 is performed.

  In step S30 corresponding to the first engine torque determination section 80c, it is determined whether or not the time during which the engine torque Tereal is equal to or greater than the drive state threshold has exceeded the drive determination time TDRVACCON after the accelerator pedal is turned on after switching to the acceleration running. Is determined. In step S30, for example, after the accelerator pedal is turned on and before the determination time in step S30, whether or not the engine torque Tereal is equal to or greater than the drive state threshold value is monitored only during the drive determination time TDRVACCON. A determination is made. If the determination in step S30 is affirmative, step S100 is executed. If the determination in step S30 is negative, step S40 is executed.

  In step S40 corresponding to the second engine torque determination unit 80d, it is determined whether or not the time during which the engine torque Tereal is equal to or less than the driven state threshold after the accelerator pedal is turned on has exceeded the driven determination time TDRVACCOFF. In step S40, for example, after the accelerator pedal is turned on and before the determination time in step S40, whether or not the engine torque Tereal is equal to or less than the driven state threshold value is monitored only during the driven determination time TDRVACCOFF. The above determination is made. Preferably, the start of the drive determination time TDRVACCOFF in step S40 is set earlier than the end of the drive determination time TDRVACCON in step S30. More preferably, the start of the drive determination time TDRVACCON in step S30 and the start of the driven determination time TDRVACCOFF in step S40 are the same. Depending on the length of the period during which the engine torque Tereal is transmitted as power after the accelerator pedal is turned on, the degree of backlash narrowing in the rotational direction of the power transmission member in the driving state changes. Therefore, in the case of the above-described preferred example, the actual narrowing of the backlash at the determination time of step S40 is smaller than the start of the driven determination time TDRVACCOFF in step S40 after the end of the drive determination time TDRVACCON in step S30. This is because the determination reflects the condition. If the determination in step S40 is affirmative, step S90 is executed. If the determination in step S40 is negative, step S100 is executed.

  In step S50 corresponding to the threshold value setting unit 80b, the drive determination value TOFF1 for FCOFF is set as the drive state threshold value, and the drive determination value TOFF2 for FCOFF is set as the drive state threshold value. Then, step S60 is performed.

  In step S60 corresponding to the first engine torque determination unit 80c, it is determined whether the time during which the engine torque Tereal is equal to or greater than the drive state threshold has exceeded the drive determination time TDRVACCON after the accelerator pedal is turned ON after the switch to the acceleration traveling. Is determined. In step S60, for example, after the accelerator pedal is turned on and before the determination time in step S60, whether or not the engine torque Tereal is equal to or greater than the drive state threshold value is monitored only during the drive determination time TDRVACCON, so that A determination is made. If the determination in step S60 is affirmative, step S100 is executed. If the determination in step S60 is negative, step S70 is executed.

  In step S70 corresponding to the second engine torque determination unit 80d, it is determined whether the time during which the engine torque Tereal is equal to or less than the driven state threshold after the accelerator pedal is turned on has exceeded the driven determination time TDRVACCOFF. In step S70, for example, after the accelerator pedal is turned on and before the determination time in step S70, whether or not the engine torque Tereal is equal to or less than the driven state threshold value is monitored only during the driven determination time TDRVACCOFF. The above determination is made. Preferably, the start of the drive determination time TDRVACCOFF in step S70 is set earlier than the end of the drive determination time TDRVACCON in step S60. More preferably, the start of the drive determination time TDRVACCON in step S60 and the start of the driven determination time TDRVACCOFF in step S70 are the same. Depending on the length of the period during which the engine torque Tereal is transmitted as power after the accelerator pedal is turned on, the degree of backlash narrowing in the rotational direction of the power transmission member in the driving state changes. Therefore, the actual narrowing of the backlash at the determination time of step S70 is better in the case of the preferred embodiment than when the start of the driven determination time TDRVACCOFF is set after the end of the drive determination time TDRVACCON in step S60. This is because the determination reflects the condition. If the determination in step S70 is affirmative, step S80 is executed. If the determination in step S70 is negative, step S100 is executed.

  In step S80 corresponding to the differential rotation determination unit 80e, it is determined whether or not the differential rotation speed NSLP is equal to or less than the differential rotation speed determination value NSLP_thr. If the determination in step S80 is affirmative, step S90 is executed. If the determination in step S80 is negative, step S100 is executed.

  In step S90 corresponding to the acceleration control unit 80f, the acceleration control in which the shock reduction control is performed is performed. And it ends.

  In step S100 corresponding to the acceleration control unit 80f, acceleration control in which the shock reduction control is not performed is performed. And it ends.

  Although the embodiments of the present invention have been described in detail with reference to the drawings, the present invention is applicable to other aspects.

  In the above-described embodiment, the power output from the engine 12 is transmitted to the automatic transmission 18 via the torque converter 14, but is not limited thereto. For example, instead of the torque converter 14, another fluid type power transmission device such as a fluid coupling (fluid coupling) having no torque amplification effect may be used.

  In the flowchart shown in FIG. 2 of the above-described embodiment, steps S30 and S60 are executed, but are not necessarily executed. For example, steps S30 and S60 may be omitted, only the driven state threshold may be set in steps S20 and S50, step S40 may be executed after step S20 is executed, and step S70 may be executed after step S50 is executed. . By setting the driven state threshold value in the second deceleration control to be higher than the driven state threshold value in the first deceleration control, the vehicle 10 is driven and controlled by steps S40, S70, and S80. The accuracy of determining which of the driving states is in is improved.

  In the flowchart shown in FIG. 2 of the above-described embodiment, in steps S30 and S60, it is determined whether the time during which the engine torque Tereal is equal to or greater than the drive state threshold after the accelerator pedal is turned on exceeds the drive determination time TDRVACCON, In steps S40 and S70, it is determined whether or not the time during which the engine torque Tereal is equal to or less than the driven state threshold value after the accelerator pedal is turned on exceeds the driven determination time TDRVACCOFF. However, the present invention is not limited to this. For example, since the amount of operation of the accelerator pedal by the driver when switching from coasting to acceleration traveling is often the same for a while after the accelerator pedal is turned on, the determination times at steps S30, S40, S60, and S70 (for example, Alternatively, it may be determined whether the engine torque Tereal at the drive determination time TDRVACCON and the drive determination time TDRVACCOFF is equal to or greater than the drive state threshold or equal to or less than the drive state threshold. Even in such a determination, the driven state threshold value in the second deceleration control is set to be higher than the driven state threshold value in the first deceleration control. As a result, the accuracy of determining whether the vehicle 10 is in the driving state or the driven state is improved.

  It should be noted that the above is merely an embodiment, and that the present invention can be implemented in various modified and improved forms based on the knowledge of those skilled in the art.

80: Electronic control device (control device)
80a: fuel cut determination unit 80b: threshold setting unit 80d: second engine torque determination unit (driven state determination unit)
80f: acceleration control unit Tereal: engine torque TON2: FCON driven determination value (predetermined first determination value)
TOFF2: FCOFF driven determination value (predetermined second determination value)

Claims (1)

A control device for a vehicle that selectively performs one of first deceleration control with fuel cut and second deceleration control without fuel cut as deceleration control in coasting,
A fuel cut determination unit that determines which of the first deceleration control and the second deceleration control the coasting before switching to the acceleration traveling;
When the fuel cut determination unit determines that the control is the first deceleration control, a predetermined first determination value is set as a driven state threshold value, and the fuel cut determination unit determines that the control is the second deceleration control. A threshold setting unit that sets a predetermined second determination value higher than the first determination value as the driven state threshold;
A driven state determination unit configured to determine whether an engine torque after switching to the accelerated traveling is equal to or less than the driven state threshold value set by the threshold value setting unit. apparatus.

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