JP7123304B2 - vehicle controller - Google Patents

Description

The present invention relates to a vehicle control device that controls the torque of a drive source based on the degree of accelerator opening.

Conventionally, a target torque for an engine (drive source) of a vehicle is set based on the accelerator opening corresponding to the operation of the accelerator pedal by the driver, and the engine is controlled based on this target torque. However, when the vehicle is accelerating or decelerating, if the target torque corresponding to the accelerator opening is used as it is to control the engine, the torsion of the drive shaft that drives the wheels and the torque of the engine are transmitted to the power transmission system. Body vibration may occur due to backlash of the internal gears.

In general, in order to suppress such vehicle body vibrations, processing is performed to moderate changes in the target torque during acceleration and deceleration (such as processing to completely or partially smooth the rise or fall of the target torque). was For example, Patent Literature 1 discloses a technique of obtaining the rate of change of the torsion angle of the drive shaft and temporarily decreasing or increasing the torque when the rate of change is greater than the allowable limit.

Japanese Patent Application Laid-Open No. 2006-17001

However, as described above, if the target torque change is moderated during acceleration/deceleration, the vibration of the vehicle body can be suppressed, but the responsiveness (transient response) during acceleration/deceleration is reduced. There is a detrimental effect that performance and deceleration performance are degraded. Therefore, it is desirable to both suppress vehicle body vibration and ensure transient response.

By the way, during deceleration of the vehicle, vehicle body vibration occurs depending on the torsion state of the drive shaft. Therefore, it is desirable to appropriately determine the torsion state of the drive shaft during deceleration and perform control for suppressing vehicle body vibration.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems of the prior art, and is to appropriately suppress vehicle body vibration by controlling the torque of a drive source according to the torsion angle of a drive shaft during deceleration. It is an object of the present invention to provide a vehicle control device capable of

In order to achieve the above objects, the present invention provides a vehicle control apparatus comprising an accelerator opening sensor for detecting an accelerator opening, a torque adjusting mechanism for adjusting torque of a driving source of the vehicle, an accelerator opening and a controller for controlling the torque adjustment mechanism based on the accelerator opening detected by the sensor, wherein the controller adjusts the torque so as to reduce the torque of the driving source when the accelerator opening becomes substantially zero. After controlling the mechanism, the actual torsion angle of the drive shaft that drives the wheels is obtained based on the difference between the angular velocity on the drive source side and the angular velocity on the vehicle wheel side, and this actual torsion angle increases from 0 to the deceleration direction of the wheels. The controller is configured to control the torque adjustment mechanism so as to increase the torque of the drive source when the torque changes to the deceleration direction, and after the torque of the drive source is increased, the actual torsion angle reaches the peak in the deceleration direction. It is characterized by controlling the torque adjustment mechanism so as to reduce the torque of the drive source again when the torque reaches the target.
In the present invention configured as described above, the controller reduces the torque of the drive source when the accelerator opening becomes almost 0 (opening corresponding to accelerator off), and then the angular velocity on the drive source side and the wheel side The actual torsion angle of the drive shaft is determined based on the difference from the angular velocity of , and the torque is increased when the actual torsion angle changes from 0 toward the deceleration direction. When the actual torsion angle changes from 0 to the deceleration direction in this way, the backlash of the gears in the power transmission system to which the torque from the drive source is transmitted is reduced. Therefore, by increasing the torque of the drive source at this time, it is possible to appropriately suppress vehicle body vibration (shock that eliminates backlash) that occurs when the backlash of the gears is reduced during deceleration. Further, according to the present invention, it is possible to suppress the twisting of the drive shaft after the actual torsion angle reaches the peak in the deceleration direction, and it is possible to appropriately suppress the vibration caused by the torsion of the drive shaft. .

In order to achieve the above objects, the present invention provides a vehicle control apparatus comprising an accelerator opening sensor for detecting an accelerator opening, a torque adjusting mechanism for adjusting torque of a driving source of the vehicle, an accelerator opening and a controller that controls the torque adjustment mechanism based on the accelerator opening detected by the sensor, wherein the controller determines that the driver's deceleration request is large when the accelerator opening becomes substantially zero. , after the torque of the drive source is reduced , the actual torsion angle of the drive shaft that drives the wheels, which is obtained based on the difference between the angular velocity on the drive source side and the angular velocity on the wheel side of the vehicle, changes from 0 to the deceleration direction. On the other hand, if it is determined that the deceleration request is small , the drive source is controlled when the actual torsion angle reaches the peak in the deceleration direction. characterized in that it is configured to control the torque adjustment mechanism so as to reduce the torque of the
According to the present invention configured as described above, when the deceleration request is relatively large, the deceleration request can be reliably satisfied while suppressing the vibration of the vehicle body, and when the deceleration request is relatively small, The vehicle body vibration can be effectively suppressed while satisfying the deceleration request to some extent.

In the present invention, preferably, when the controller determines that the deceleration request is small, the controller determines the deceleration request based on at least one of the angular velocity of the drive source, the torque of the drive source, and the gear stage of the transmission of the vehicle. By further determining the degree of the deceleration request, the method of decreasing the torque of the drive source when the actual torsion angle reaches the peak in the deceleration direction is changed.
According to the present invention configured as described above, it is possible to flexibly change whether to give priority to a deceleration request or to give priority to vibration suppression by changing the torque reduction method.

In the present invention, preferably, the drive source includes an engine having multiple cylinders, the torque adjustment mechanism includes a fuel adjustment device that adjusts fuel supply to each cylinder of the engine, and the controller adjusts the degree of deceleration request. Accordingly, when the actual torsion angle reaches the first peak in the deceleration direction, a method for reducing the torque of the drive source by controlling the fuel adjustment device to stop the fuel supply to all cylinders of the engine. , every time the actual torsion angle reaches a plurality of temporally continuous peaks in the deceleration direction, the torque of the drive source is increased by controlling the fuel control device so that the fuel supply to each cylinder of the engine is sequentially stopped. It is configured to switch between a lowering method and a lowering method.
In the present invention configured as described above, the former method can satisfy the deceleration request with priority over the latter method, while the latter method has a lower drive speed than the former method. Vibration caused by torsion of the shaft can be preferentially suppressed.

In the present invention, preferably, the drive source includes an engine having multiple cylinders, the torque adjustment mechanism includes a fuel adjustment device that adjusts fuel supply to each cylinder of the engine, and the controller controls the accelerator opening to approximately By controlling the fuel adjustment device to stop the fuel supply to the engine cylinder when it reaches 0, the engine torque is reduced, and after that, the actual torsion angle changes from 0 to the deceleration direction. Sometimes, it is configured to increase engine torque by controlling a fuel regulator to re-fuel a cylinder that has been de-fueled.
According to the present invention configured as described above, when the actual torsion angle changes from 0 toward the deceleration direction, the fuel supply to the cylinder to which the fuel supply has been stopped is restarted, so that the torque of the engine is appropriately increased. It is possible to reliably suppress the backlash-filled shock.

In the present invention, preferably, after increasing the engine torque, the controller again stops fuel supply to the cylinders to which fuel supply has been resumed when the actual torsion angle reaches a peak in the deceleration direction. and is configured to control the fuel conditioner.
According to the present invention configured in this way, when the actual torsional angle reaches the peak in the deceleration direction, the fuel supply to the cylinders to which the fuel supply has been resumed is stopped again, so that the torque of the engine can be appropriately increased. Vibration caused by torsion of the drive shaft can be reliably suppressed by lowering it.

In the present invention, preferably, the controller determines the angular velocity of the drive source based on the torque from the drive source, determines the angular velocity of the wheels based on the running resistance of the vehicle, and determines the actual torsion angle based on the difference between these angular velocities. configured to ask for.
According to the present invention configured in this way, the actual torsion angle can be obtained with high accuracy.

In the present invention, the controller is preferably configured to correct the angular velocity of the drive source based on the rpm of the transmission of the vehicle.
According to the present invention configured as described above, when obtaining the actual torsional angle based on the angular velocity on the drive source side and the angular velocity on the wheel side, the angular velocity on the drive source side is corrected based on the rotation speed of the transmission. can be determined more accurately.

In the present invention, preferably, the controller sets a target acceleration of the vehicle based on the accelerator opening, sets a target twist angle of the drive shaft based on the target acceleration, and sets a target torque of the drive source based on the target twist angle . and to control the torque adjustment mechanism based on the target torque.
According to the present invention configured as described above, the controller sets the target torsion angle of the drive shaft based on the target acceleration corresponding to the accelerator opening, and sets the target torque of the drive source based on this target torsion angle . to control the torque adjustment mechanism. As a result, it is possible to apply a target torque that takes into consideration the behavior of the drive shaft during acceleration and deceleration (that is, during a transient torque increase or torque decrease). It is possible to ensure responsiveness (transient responsiveness) during deceleration.

In the present invention, preferably, the controller, in order to achieve the target torsional angle, sets the target torque based on a first torque corresponding to the torsional angle of the drive shaft and a second torque corresponding to the torsional angular velocity of the drive shaft. configured to set.
According to the present invention configured in this way, it is possible to apply a target torque that appropriately takes into account the behavior of the drive shaft. By applying this target torque, an actual torsion angle corresponding to the target torsion angle can be generated appropriately, and vibration caused by torsion of the drive shaft can be effectively suppressed.

In the present invention, the target torque preferably has a time waveform such that it rises according to the first torque and temporarily decreases according to the second torque during this rising process.
According to the present invention configured in this way, it is possible to apply the target torque that more effectively takes into account the behavior of the drive shaft during the transition of torque increase or torque decrease.

In the present invention, the controller is preferably configured to correct the target torque based on the difference between the target torsion angle and the actual torsion angle.
According to the present invention configured in this manner, for example, by feedback-controlling the torque based on the difference between the target torsion angle and the actual torsion angle, the actual torsion angle corresponding to the target torsion angle can be appropriately realized. .

In the present invention, the driving source preferably includes an engine or a motor.

According to the vehicle control device of the present invention, vehicle vibration can be appropriately suppressed by controlling the torque of the drive source according to the torsion angle of the drive shaft during deceleration.

1 is a schematic configuration diagram of a vehicle to which a vehicle control device according to an embodiment of the invention is applied; FIG. 1 is a schematic configuration diagram of an engine system to which a vehicle control device according to an embodiment of the invention is applied; FIG. 1 is a block diagram showing an electrical configuration of a vehicle control device according to an embodiment of the present invention; FIG. 4 is a block diagram showing overall control according to an embodiment of the present invention; FIG. 4 is a flow chart showing overall control according to an embodiment of the present invention; FIG. 4 is an explanatory diagram schematically showing a flow from target acceleration to target torque setting in the embodiment of the present invention; FIG. 4 is an explanatory diagram specifically showing a method of setting a target torque in the embodiment of the present invention; FIG. 4 is an explanatory diagram specifically showing an actual torsion angle when a target torque is applied according to the embodiment of the present invention; FIG. 4 is an explanatory diagram of target torque correction according to the embodiment of the present invention; 4 is a flow chart showing gutter-torsion state quantity estimation processing according to the embodiment of the present invention. 4 is a time chart for explaining the effect of correcting the target torque so as to quickly complete the elimination of looseness in the embodiment of the present invention; 4 is a flow chart showing backlash elimination F/C control according to the embodiment of the present invention; FIG. 4 is an explanatory diagram of how to obtain a backlash elimination time according to the embodiment of the present invention; FIG. 10 is an explanatory diagram of command timing of F/C for suppressing looseness shock according to the embodiment of the present invention; 4 is a time chart for explaining the effect of backlash elimination F/C control according to the embodiment of the present invention; 4 is a flow chart showing torque F/C control according to an embodiment of the present invention; 4 is a flow chart illustrating rattle twist control according to an embodiment of the present invention. 4 is a time chart showing first control of backlash torsion control according to the embodiment of the present invention; 4 is a time chart showing second control of backlash torsion control according to the embodiment of the present invention; 5 is a time chart showing third control of backlash torsion control according to the embodiment of the present invention; 4 is a time chart showing fourth control of backlash torsion control according to the embodiment of the present invention; 1 is a schematic configuration diagram of a vehicle to which a vehicle control device according to a modification of an embodiment of the invention is applied; FIG.

A vehicle control device according to an embodiment of the present invention will be described below with reference to the accompanying drawings.

<Device configuration>
First, with reference to FIG. 1, an outline of a vehicle to which a vehicle control device according to an embodiment of the invention is applied will be described. FIG. 1 is a schematic configuration diagram of a vehicle to which a vehicle control device according to an embodiment of the invention is applied.

As shown in FIG. 1, a vehicle 500 mainly includes an engine system 100 including an engine (driving source) that generates driving force, and a transmission 204 that changes the rotation speed of the engine of the engine system 100. , a power transmission system 207 for transmitting the driving force from the transmission 204 to the downstream side, a drive shaft 209 for driving the wheels 210 by the driving force from the power transmission system 207, and the wheels 210.

The output shaft of engine system 100 and the rotation shaft of transmission 204 are coaxially connected by shaft 201 via clutch 202 that can be connected and disconnected. Clutch 202 is a dry multi-plate clutch capable of changing the transmission torque capacity by continuously or stepwise controlling the flow rate of clutch operating oil and clutch operating oil pressure by a motor (not shown). A flywheel having a predetermined weight is arranged on the shaft 201 (not shown). Clutch 202 may be formed inside transmission 204 as long as it is capable of intermittently transmitting driving force between engine system 100 and transmission 204 .

A driving force is input to the power transmission system 207 via an output shaft 206 of the transmission 204 . The power transmission system 207 includes a differential gear that distributes the driving force to the pair of left and right wheels 210, a final gear, and the like.

Next, an engine system to which the vehicle control device according to the embodiment of the present invention is applied will be described with reference to FIGS. 2 and 3. FIG. FIG. 2 is a schematic configuration diagram of an engine system to which the vehicle control device according to the embodiment of the invention is applied, and FIG. 3 is a block diagram showing the electrical configuration of the vehicle control device according to the embodiment of the invention. be.

As shown in FIGS. 2 and 3, the engine system 100 mainly includes an intake passage 1 through which intake air (air) introduced from the outside passes; intake air supplied from the intake passage 1; An engine 10 (specifically, a gasoline engine) that generates driving force for the vehicle 500 by burning the air-fuel mixture with the fuel supplied from the valve 13, and an exhaust that discharges the exhaust gas generated by the combustion in the engine 10. It has a passageway 25, sensors 30-39 for detecting various conditions relating to the engine system 100, and a PCM 50 for controlling the engine system 100 as a whole.

The intake passage 1 has, in order from the upstream side, an air cleaner 3 for purifying intake air introduced from the outside, a throttle valve 5 for adjusting the amount of intake air passing through (intake air amount), and a temporary supply of intake air to the engine 10. A surge tank 7 is provided to store the power.

The engine 10 mainly includes an intake valve 12 that introduces the intake air supplied from the intake passage 1 into the cylinder 11, a fuel injection valve 13 that injects fuel into the cylinder 11, and the intake air supplied into the cylinder 11. A spark plug 14 that ignites the air-fuel mixture with the fuel, a piston 15 that reciprocates due to combustion of the air-fuel mixture in the cylinder 11, a crankshaft 16 that rotates due to the reciprocating motion of the piston 15, and a mixture in the cylinder 11. and an exhaust valve 17 for discharging exhaust gas generated by combustion of air to the exhaust passage 25 . Although only one cylinder 11 of the engine 10 is shown in FIG. 2, the engine 10 actually has a plurality of cylinders 11 (for example, four cylinders).

In addition, the engine 10 sets the operating timings (corresponding to valve phases) of the intake valves 12 and the exhaust valves 17 to a variable intake valve mechanism 18 and a variable exhaust valve mechanism as variable valve timing mechanisms. 19 are variably configured. As the variable intake valve mechanism 18 and the variable exhaust valve mechanism 19, various known types can be applied. You can change the timing.

The exhaust passage 25 is mainly provided with exhaust purification catalysts 26a and 26b having an exhaust gas purification function, such as a NOx catalyst, a three-way catalyst, and an oxidation catalyst.

The engine system 100 is also provided with sensors 30 to 39 that detect various states of the engine system 100 . Specifically, these sensors 30 to 39 are as follows. The accelerator opening sensor 30 detects the accelerator opening, which is the opening of the accelerator pedal (corresponding to the amount of depression of the accelerator pedal by the driver). The airflow sensor 31 detects the amount of intake air corresponding to the flow rate of intake air passing through the intake passage 1 . A throttle opening sensor 32 detects the throttle opening, which is the opening of the throttle valve 5 . The pressure sensor 33 detects an intake manifold pressure (intake manifold pressure) corresponding to the pressure of intake air supplied to the engine 10 . A crank angle sensor 34 detects the crank angle of the crankshaft 16 . A water temperature sensor 35 detects the water temperature, which is the temperature of cooling water for cooling the engine 10 . The temperature sensor 36 detects the in-cylinder temperature, which is the temperature inside the cylinder of the engine 10 . The cam angle sensors 37 and 38 detect operation timings including closing timings of the intake valve 12 and the exhaust valve 17, respectively. Vehicle speed sensor 39 detects the speed of vehicle 500 (vehicle speed). Transmission rotation speed sensor 40 detects the rotation speed of transmission 204, that is, the rotation speed of clutch 202 (more specifically, the rotation speed of a shaft (P-axis) of shaft 201 on the transmission 204 side). These various sensors 30-40 output detection signals S130-S140 corresponding to the detected parameters to the PCM 50, respectively.

The PCM 50 controls components within the engine system 100 based on the detection signals S130-S140 input from the various sensors 30-40 described above. Specifically, as shown in FIG. A control signal S114 is supplied to the ignition plug 14 to control the ignition timing, and a control signal S118 is supplied to each of the variable intake valve mechanism 18 and the variable exhaust valve mechanism 19. , S119 to control the operation timings of the intake valve 12 and the exhaust valve 17 . The throttle valve 5, the fuel injection valve 13, the spark plug 14, the variable intake valve mechanism 18, the variable exhaust valve mechanism 19, etc. correspond to the "torque adjusting mechanism" in the present invention. In particular, the throttle valve 5 corresponds to the "air amount adjusting device" of the present invention, and the fuel injection valve 13 corresponds to the "fuel adjusting device" of the present invention.

Such a PCM 50 includes one or more processors, various programs interpreted and executed on the processor (including basic control programs such as an OS, and application programs that are started on the OS and implement specific functions), and programs and a computer with internal memory such as ROM and RAM for storing various data. Although the details will be described later, the PCM 50 corresponds to the "controller" in the present invention.

<Control contents>
Below, the contents of the control executed by the PCM 50 described above in this embodiment will be described.

(Overall control)
First, with reference to FIGS. 4 and 5, an outline of overall control contents executed by the PCM 50 in this embodiment will be described. FIG. 4 is a block diagram showing overall control according to the embodiment of the present invention, and FIG. 5 is a flow chart showing overall control according to the embodiment of the present invention.

As shown in FIG. 4, the PCM 50 first sets the target acceleration based on the accelerator opening. For example, the PCM 50 sets the target acceleration corresponding to the current vehicle speed and accelerator opening using a map indicating the relationship between the accelerator opening and the target acceleration defined for each vehicle speed. The PCM 50 then converts this target acceleration into a target twist angle of the drive shaft 209 . Specifically, the PCM 50 converts acceleration to wheel torque using equation (1) below, and converts this wheel torque to twist angle using equation (2).
T _w =M _v ×r _w ×a Formula (1)
θ= _Tw / _Kb formula (2)
Here, "T _w " is the wheel torque, "M _v " is the vehicle weight, "r _w " is the wheel radius, "a" is the acceleration, and "θ" is the torsional angle of the drive shaft. and "K _b " is the stiffness of the drive shaft.

Next, the PCM 50 applies a predetermined feedforward gain to the target twist angle, and obtains a target torque corresponding to the target twist angle thus obtained. Specifically, PCM 50 uses an inverse model of a predetermined driving system model for vehicle 500 to obtain a target torque to be output from engine 10 in order to achieve a target twist angle. Since this target torque is obtained by the feedforward process, the target torque will hereinafter be referred to as "FF target torque" as appropriate.

Next, from the viewpoint of suppressing modeling errors and disturbances (such as running resistance), the PCM 50 calculates a target torque (hereinafter referred to as "FB target torque" as appropriate) obtained for controlling the torque of the engine 10 by feedback processing. corrects the above FF target torque. Then, the PCM 50 determines the target air amount, the target ignition timing, the target fuel injection amount, etc. in order to output the corrected target torque (hereinafter referred to as "final target torque" as appropriate) from the engine 10 ( A target power generation amount of the alternator may also be included), and torque adjustment mechanisms such as the throttle valve 5, the fuel injection valve 13, and the spark plug 14 of the engine system 100 are controlled. In other words, the PCM 50 controls the engine 10 by distributing methods for achieving the final target torque. After that, combustion actually occurs in the engine 10 to generate actual torque, and this actual torque appears as the actual vehicle behavior.

Next, using a predetermined engine torque model, the PCM 50 uses various parameters (ignition timing, target air-fuel ratio, etc.) used to control the engine 10 and various sensor values corresponding to the actual vehicle behavior due to the fuel in the engine 10. The current torque generated by the fuel in the engine 10 is estimated from (the intake air amount by the air flow sensor 31, the intake manifold pressure by the pressure sensor 33, the engine speed by the crank angle sensor 34, etc.).

In addition to estimating the torque, the PCM 50 uses a predetermined running resistance model to apply torque to the vehicle 500 based on the vehicle speed detected by the vehicle speed sensor 39 and the brake pressure corresponding to the brake operation by the driver. Estimate the applied running resistance. The running resistance includes not only air resistance, rolling resistance and slope resistance, but also the braking force of the brake when the driver performs a braking operation.

PCM 50 then uses a predetermined driving system model for vehicle 500 to estimate the actual torsional angle of drive shaft 209 from the torque and running resistance estimated as described above. Specifically, the PCM 50 obtains the angular velocity on the engine 10 side (the angular velocity of the inertia on the engine 10 side) from the estimated torque, obtains the angular velocity on the wheel side from the estimated running resistance, and based on the difference between these angular velocities, Estimate the twist angle. In this case, the PCM 50 also uses the rotation speed of the clutch 202 (the rotation speed of the P-axis) detected by the transmission rotation speed sensor 40 to estimate the twist angle. Specifically, the PCM 50 controls the angular velocity (estimated (equivalent to the calculated engine speed) is corrected. In addition, below, the angular velocity on the engine 10 side is appropriately referred to as the engine speed.

Next, the PCM 50 obtains the above-mentioned FB target torque based on the torsion angle thus estimated (estimated torsion angle) and the initially set target torsion angle. Specifically, the PCM 50 obtains the FB target torque by applying a predetermined feedback gain to a value obtained by subtracting the estimated torsion angle from the target torsion angle. Then, the PCM 50 obtains the final target torque by correcting the above-described FF target torque with this FB target torque (typically by adding the FB target torque to the FF target torque).

Next, with reference to FIG. 5, an overview of the overall control flow according to the embodiment of the present invention will be described. The process according to the flowchart shown in FIG. 5 is started when the ignition of the vehicle 500 is turned on and the power of the PCM 50 or the like is turned on, and is repeatedly executed at a predetermined cycle (for example, 50 ms).

First, in step S<b>101 , the PCM 50 acquires various information about the vehicle 500 . Specifically, the PCM 50 acquires parameters detected by the various sensors 30 to 40 described above.

Next, in step S102, the PCM 50 determines whether or not the accelerator opening detected by the accelerator opening sensor 30 is not zero. That is, the PCM 50 determines whether or not the accelerator pedal is depressed by the driver. As a result, when the accelerator opening is not 0 (step S102: Yes), the PCM 50 proceeds to steps S103 and S109. The processing after step S103 (processing of steps S103 to S108) and the processing after step S109 (processing of steps S109 and S110) are executed in parallel.

The specific contents of the processing of steps S103 to S108 are as described with reference to FIG. That is, first, in step S103, the PCM 50 obtains the target acceleration from the accelerator opening detected by the accelerator opening sensor 30. FIG. Next, in step S104, the PCM 50 obtains a target twist angle corresponding to this target acceleration. Next, in step S105, the PCM 50 obtains the FF target torque to be output from the engine 10 in order to achieve this target twist angle. Next, in step S106, the PCM 50 obtains the FB target torque for correcting this FF target torque (strictly speaking, the FB target torque is calculated in parallel with the calculation of the FF target torque). Next, in step S107, the PCM 50 obtains the final target torque by correcting the FF target torque with the FB target torque. Next, at step S108, the PCM 50 controls the engine 10 based on this final target torque.

On the other hand, in step S109, the PCM 50 executes a backlash-torsion state quantity estimation process for estimating the backlash state of the gears in the power transmission system 207 and the torsion state of the drive shaft 209. FIG. The PCM 50 utilizes the result of this backlash-torsion state quantity estimation processing when obtaining the FB target torque in step S106 described above. In particular, PCM 50 applies the results of the gutter-torsion state quantity estimation process in estimating the actual torsion angle of drive shaft 209 .

Next, in step S110, the PCM 50 controls the vibration of the vehicle body that occurs when the gears in the power transmission system 207 become loose (hereinafter referred to as "backlash reduction shock"). Based on the result of the state quantity estimating process, backlash elimination F/C control is executed to stop fuel supply to the engine 10 (fuel cut (F/C)) when backlash is reduced.

On the other hand, if the accelerator opening is 0 in step S102 (step S102: No), that is, if the accelerator pedal is not depressed by the driver, the PCM 50 proceeds to steps S111 and S113. The processing after step S111 (the processing of steps S111 and S112) and the processing of step S113 are executed in parallel.

In step S113, the PCM 50 executes the play-torsion state quantity estimation process in the same manner as in step S109. On the other hand, in step S111, the PCM 50 executes torque F/C control for stopping (F/C) the fuel supply to the engine 10 because the accelerator opening is 0 (accelerator off). Next, in step S112, the PCM 50, based on the result of the backlash-torsion state quantity estimation process in step S113, determines that the vibration of the vehicle body and the torsion of the drive shaft 209 that occur when the backlash of the gears in the power transmission system 207 is blocked. Backlash twist control is executed to suppress vehicle body vibration.

(Target torque setting)
Next, a method for setting the target torque in this embodiment will be specifically described with reference to FIGS. 6 to 8. FIG.

FIG. 6 is an explanatory diagram schematically showing the flow from target acceleration to target torque setting in the embodiment of the present invention. First, the PCM 50 sets a target acceleration based on the accelerator opening detected by the accelerator opening sensor 30 . For example, the PCM 50 sets the target acceleration corresponding to the current vehicle speed and accelerator opening using a map indicating the relationship between the accelerator opening and the target acceleration defined for each vehicle speed.

PCM 50 then converts the target acceleration to a target twist angle of drive shaft 209 . Specifically, the PCM 50 converts the target acceleration into the wheel torque using the formulas (1) and (2) described above, and then converts the wheel torque into the target twist angle. Basically, the form of change over time in the target torsion angle is similar to the form of change over time in the target acceleration. Next, the PCM 50 uses an inverse model of a predetermined drive system model for the vehicle 500 to obtain a target torque to be output from the engine 10 in order to achieve the target torsion angle (the target torque obtained here is the FF target torque). In this embodiment, the form of temporal change of the target torque is partially different from the form of temporal change of the target torsion angle.

Next, FIG. 7 is an explanatory diagram specifically showing a method of setting the target torque in the embodiment of the present invention. As shown in FIG. 7, roughly speaking, the PCM 50 differentiates the torsional angular torque (first torque) corresponding to the torsional angle (target torsional angle) of the drive shaft 209 and the torsional angular velocity (target torsional angle) of the drive shaft 209. The target torque is set based on the torsional angular velocity torque (second torque) corresponding to the object). Specifically, the PCM 50 sets the target torque by adding these torques. As a result, the target torque generally increases according to the torsional angular torque, but has a time waveform such that it temporarily decreases according to the torsional angular velocity torque during this rising process.

Such a shape of the target torque is such that when torque is applied to the drive shaft 209, energy is temporarily stored in the drive shaft 209 in the middle of the torque increase, and the torsion of the drive shaft 209 is temporarily stopped. It corresponds to the behavior of the drive shaft 209 such that the drive shaft 209 twists as the energy in the shaft 209 is released. In the present embodiment, by using an inverse model of the drive system model, a target torque that takes into account the behavior of the drive shaft 209 when such torque is applied is applied.

More specifically, the PCM 50 obtains the target torque using the following equation (3) representing an inverse model of the drivetrain model.

In equation (3), "T _e " is the engine torque (target torque), "T _v " is the running resistance torque, and "θ" is the torsion angle of the drive shaft ( Dots represent torsional angular velocity obtained by differentiating the torsional angle once and torsional angular acceleration obtained by differentiating the torsional angle twice), “η” is the gear ratio, and “J _e ” is the inertia of the engine. , "J _v " is the inertia of the vehicle body, "k" is the stiffness of the drive shaft, and "c" is the damping of the drive shaft. In equation (3), the third term on the right side corresponds to torsional angular torque corresponding to the torsional angle, and the second term on the right side corresponds to torsional angular velocity torque corresponding to torsional angular velocity. Basically, in equation (3), the torsional angular torque term and the torsional angular velocity torque term are dominant, so that the target torque is determined according to the torsional angular torque and the torsional angular velocity torque as shown in FIG. It becomes a time waveform.

Here, the above formula (3) is defined by the following concept. That is, in the present embodiment, the target torque is set based on the target torsion angle so as to suppress vehicle body vibration due to torsion of the drive shaft 209 and ensure transient responsiveness during acceleration and deceleration. In particular, in order to suppress vibration due to torsion of the drive shaft 209, that is, to keep the torsional angle within a predetermined value or less, it is necessary to keep the torsional velocity within a predetermined value or less. need to accommodate. Since this torsional angular acceleration is defined by "torque x inertia", it is necessary to keep the amplitude of the torque within a certain level. In addition to this way of thinking, ensuring transient responsiveness is added to define equation (3) for determining the ideal engine torque.

Next, FIG. 8 is an explanatory diagram specifically showing the actual torsion angle when the target torque is applied according to the embodiment of the present invention. In FIG. 8 , the solid line indicates the target torque and actual torsion angle according to this embodiment, and the dashed line indicates the target torque and actual torsion angle according to Comparative Example 1. In FIG. In the present embodiment, a target torque having a time waveform such that the torque temporarily decreases in the process of increasing the torque is applied. This takes into consideration the actual behavior of the drive shaft 209 when torque is applied. By applying such a target torque, an actual torsion angle corresponding to the target torsion angle (see FIG. 6) is appropriately generated. In particular, according to this embodiment, since the drive shaft 209 is smoothly twisted, the vibration caused by the twist of the drive shaft 209 is suppressed.

On the other hand, in Comparative Example 1, a target torque having a form similar to the target twist angle (see FIG. 6) is applied. That is, in Comparative Example 1, a target torque having a time waveform in which the torque rises as it is without decreasing in the middle is applied. This corresponds to treating the drive shaft 209 as a rigid body without considering the torsion of the drive shaft 209 . If such a target torque is applied, the actual twist angle will overshoot. This is due to over-torque. As a result, according to Comparative Example 1, vibration due to torsion of the drive shaft 209 occurs.

Conventionally, a target torque as indicated by the dashed-dotted line in FIG. 8 has been applied in order to suppress the occurrence of vibration as in Comparative Example 1 (hereinafter referred to as "Comparative Example 2"). Specifically, in Comparative Example 2, a target torque whose rise is delayed to some extent is applied. According to such a target torque, the actual torsion angle is gently twisted (not shown), so that the vibration caused by the torsion of the drive shaft 209 can be suppressed. However, the responsiveness (transient responsiveness) during acceleration and deceleration is degraded. In contrast, in the present embodiment, the target torque is applied without delaying the rise of the target torque, taking into account the actual behavior of the drive shaft 209 when the torque is applied. and can be appropriately compatible with each other.

Note that the target torque set as described above may be corrected in consideration of the response delay of the torque adjustment mechanism that adjusts the torque of the engine 10 . Specifically, the PCM 50 preferably corrects the target torque so as to compensate for the response delay of the throttle valve 5 (air amount adjusting device) that adjusts the amount of air supplied to the engine 10 .

FIG. 9 is an explanatory diagram of correction of the target torque according to the embodiment of the present invention. The upper graph in FIG. 9 shows the accelerator opening (solid line) corresponding to the accelerator operation by the driver and the acceleration (broken line) to be generated from the vehicle 500 according to this accelerator opening. As shown in this graph, when acceleration is generated after an appropriate time T11 (for example, about 150 msec) from the accelerator operation by the driver, the driver tends to feel that the vehicle 500 is appropriately accelerating in response to the accelerator operation.

The graph at the bottom of FIG. 9 shows the actual torque (solid line) of the engine 10 required to generate the above acceleration from the vehicle 500 and the target torque (dashed line) to be applied to achieve this actual torque. is shown. When the torque of the engine 10 is increased in accordance with the accelerator operation, control is performed to increase the opening of the throttle valve 5 so as to increase the amount of air supplied to the engine 10 . There is a time delay between the issuance of such a control command and the actual change in torque. This time delay corresponds to the response delay of the throttle valve 5 or the like.

Therefore, in this embodiment, the PCM 50 advances the control command for the throttle valve 5 by a time T12 (for example, about 100 msec) corresponding to such a response delay, and reduces the actual torque to be output from the engine 10 by the time T12. The torque that is put out in advance is applied as the target torque. That is, the PCM 50 advances the target torque set from the target torsion angle as described above by the time T12 corresponding to the response delay of the throttle valve 5 . As a result, it is possible to appropriately prevent the torque output of the engine 10 from being delayed with respect to the driver's acceleration request due to the response delay of the throttle valve 5 . Although FIG. 9 shows correction of the target torque during acceleration, such correction of the target torque can also be applied during deceleration.

(Gutter-torsion state quantity estimation processing)
Next, the gutter-torsion state quantity estimation processing performed in steps S109 and S113 of FIG. 5 will be specifically described. As described above, this gutter-torsion state quantity estimation processing is performed to estimate the state of play of the gears (differential gear, final gear, etc.) in the power transmission system 207 and the torsion state of the drive shaft 209 .

FIG. 10 is a flow chart showing gutter-torsion state quantity estimation processing according to the embodiment of the present invention. Typically, this process is started when vehicle 500 starts from a stopped state. Here, the backlash of the gear and the torsion of the drive shaft 209 are as follows: when there is backlash in the gear, the drive shaft 209 is not twisted; is clogged). Therefore, in the play-torsion state quantity estimation process according to the present embodiment, the process for estimating the state of gear play (steps S201 to S206, S212) and the process for estimating the torsion state of the drive shaft 209 ( Steps S207 to S211) are configured to be executed by switching.

When the play-torsion state quantity estimation process is started, first, in step S201, the PCM 50 sets a "play determination flag" indicating whether or not there is play in the gears in the power transmission system 207 to ON. The situation in which step S201 is executed (for example, when starting from a stopped state) is a situation in which backlash exists, in other words, a situation in which backlash is not present, so the PCM 50 sets the backlash determination flag to ON. . Also, the PCM 50 sets the initial play angle indicating the initial position of the gear play to zero.

Next, in step S202, the PCM 50 corrects the target torque of the engine 10. FIG. Specifically, the PCM 50 has a value (>0) in the drive direction after the torsion angle becomes 0 or a value (<0)), correcting the target torque. In particular, the PCM 50 corrects the target torque in the increasing direction when the target torque is changing in the increasing direction, and decreases the target torque when the target torque is changing in the decreasing direction. Correct the direction. For example, when the target torque is increasing, the PCM 50 increases the target torque by a preset amount, and when the target torque is decreasing, the PCM 50 increases the target torque by a predetermined amount. The target torque is reduced by a preset amount.

Next, in step S203, the PCM 50 estimates the torque of the engine 10 using a predetermined engine torque model, obtains the angular velocity of the engine 10 from this torque (the angular velocity of the inertia of the engine 10), The running resistance is estimated using the resistance model, and the angular velocity of the wheel is obtained from the running resistance. In this case, the PCM 50 may correct the angular velocity of the engine 10 using the rotation speed of the clutch 202 (the rotation speed of the P-axis) detected by the transmission rotation speed sensor 40 .

Next, in step S204, the PCM 50 obtains the change angle of gear backlash based on the difference between the engine 10-side angular speed and the wheel-side angular speed obtained in step S203. The PCM 50 obtains a larger backlash change angle as the angular velocity difference is larger.

Next, in step S205, the PCM 50 obtains the current backlash angle based on the backlash change angle obtained in step S204. Specifically, the PCM 50 obtains the current backlash angle by adding the backlash change angle to the previously determined backlash angle.

Next, in step S206, the PCM 50 determines whether or not the backlash angle determined in step S205 exceeds the backlash design value. This play design value (for example, about 3 degrees) corresponds to the play angle of the gear in which the play is reduced. Therefore, the determination in step S206 corresponds to the determination of whether or not the backlash has been eliminated. In step S206, if it is determined that the backlash angle has not exceeded the backlash design value (step S206: No), that is, if the backlash is not reduced, the PCM 50 returns to step S203 and executes the processes after step S203 again. do.

On the other hand, if it is determined in step S206 that the backlash angle has exceeded the backlash design value (step S206: Yes), that is, if backlash is reduced, the PCM 50 proceeds to step S207. In this case, the PCM 50 turns off the backlash determination flag (step S207). Further, since the drive shaft 209 is not yet twisted at the time when the looseness is eliminated, the PCM 50 sets the initial twist angle indicating the initial twist angle of the drive shaft 209 to 0 in this step S207.

Next, in step S208, the PCM 50 estimates the torque of the engine 10 using a predetermined engine torque model, and obtains the angular velocity of the engine 10 from this torque (the angular velocity of the inertia of the engine 10). The running resistance is estimated using the resistance model, and the angular velocity of the wheel is obtained from the running resistance. In this case, the PCM 50 may correct the angular velocity of the engine 10 using the rotation speed of the clutch 202 (the rotation speed of the P-axis) detected by the transmission rotation speed sensor 40 .

Next, in step S209, the PCM 50 obtains the torsion change angle of the drive shaft 209 based on the difference between the engine 10-side angular speed and the wheel-side angular speed obtained in step S208. The PCM 50 obtains a larger twist change angle as the angular velocity difference is larger.

Next, in step S210, the PCM 50 obtains the current twist angle based on the twist change angle obtained in step S209. Specifically, the PCM 50 obtains the current twist angle by adding the twist change angle to the previously obtained twist angle.

Next, in step S211, the PCM 50 determines whether or not the twist angle obtained in step S210 is 0, in other words, determines whether or not the drive shaft 209 is twisted. If it is not determined in step S211 that the torsion angle is 0 (step S211: No), that is, if the drive shaft 209 is twisted, the PCM 50 returns to step S208 and executes the processes after step S208 again. .

On the other hand, if it is determined in step S211 that the twist angle is 0 (step S211: Yes), that is, if the drive shaft 209 is not twisted, the PCM 50 proceeds to step S212. In this case, the PCM 50 turns on the backlash determination flag (step S212). In other words, after this, since the backlash of the gear starts to be reduced, the PCM 50 switches the backlash determination flag from off to on. Further, when the torsion angle becomes 0, the backlash is still closed, so the PCM 50 sets the initial backlash angle to the above-described backlash design value in step S212. The backlash design value on the acceleration side (driving side) is a positive value, and the backlash design value on the deceleration side is a negative value.

After step S212, the PCM 50 ends the gutter-torsion state quantity estimation processing and returns to the main routine (FIG. 5).

Next, with reference to FIG. 11, the effect of correcting the target torque so as to quickly complete the elimination of the looseness of the gear (see step S202 in FIG. 10) will be described. FIG. 11 shows, from top to bottom, vehicle speed, accelerator opening, acceleration (solid line is actual acceleration, dashed line is target acceleration), torque (solid line is target torque, dashed line is actual torque), torsion angle (solid line is target torsion angle, dashed line). is an estimated torsion angle), gear backlash angle (estimated backlash angle), backlash speed (solid line is estimated backlash speed, dashed line is target backlash speed), backlash speed F/B amount, torque F/B amount. ing. FIG. 11 illustrates the acceleration of vehicle 500 .

As shown in FIG. 11, when the backlash angle starts to change due to the acceleration of the vehicle 500, that is, when the backlash of the gears starts (at this time, the torsion angle of the drive shaft 209 becomes 0). , the PCM 50 corrects the target torque so as to quickly complete the reduction of looseness in the gear. In the situation shown in FIG. 11, the target torque changes in the increasing direction, so the PCM 50 corrects the target torque in the increasing direction (see arrow A11).

Then, the PCM 50 determines the target torque according to the following procedure while the looseness of the gear is reduced. In other words, the PCM 50 estimates the speed at which the gears are full of backlash (estimated backlash speed), and sets the target backlash speed based on this estimation result. Then, the PCM 50 sets the backlash speed F/B amount for controlling the backlash speed based on the difference between the target backlash speed and the estimated backlash speed, and calculates the torque F/B amount according to this backlash speed F/B amount. Applies to target torque. As a result, the target torque is temporarily reduced at the timing when the looseness of the gear is completely eliminated (see arrow A12). As a result, it is possible to suppress the vibration (backlash reduction shock) that occurs when the backlash is completely eliminated.

(Removing backlash F/C control)
Next, the backlash elimination F/C control performed in step S110 of FIG. 5 will be specifically described. As this backlash elimination F/C control, the PCM 50 stops the fuel supply to the engine 10 (F/ C). In particular, in the present embodiment, the PCM 50 corrects the target torque so as to quickly complete the elimination of the looseness of the gears as described above. In order to suppress it, looseness reduction F/C control is executed to reduce the torque. Here, as a method of realizing a reduction in torque for suppressing backlash shock, a method of retarding the ignition timing can be considered other than the F/C. Since there is a high possibility that the desired torque reduction cannot be achieved, in this embodiment, F/C is adopted as a torque reduction method for suppressing backlash shock.

FIG. 12 is a flow chart showing backlash elimination F/C control according to the embodiment of the present invention. Typically, this looseness F/C control is executed when vehicle 500 is accelerating.

When the backlash elimination F/C control is started, first, in step S301, the PCM 50 determines whether the backlash of the gear will be eliminated after three ignitions (360deg CA) of the engine 10 based on the result of the above-described backlash-torsion state quantity estimation processing. determine whether or not Specifically, the PCM 50 calculates the time required from the start of gear elimination (backlash entry) to the completion of elimination of backlash (hereinafter referred to as "backlash elimination time") based on the backlash-torsion state quantity estimation process. Then, at the start of elimination of looseness, a timer corresponding to the time for eliminating looseness is set and countdown is carried out. Then, the PCM 50 determines whether or not the current timing is 3 ignitions before the end of the countdown of this timer (the end of the looseness elimination timing). It should be noted that the reason why the timing three ignitions before the completion of backlash elimination is determined is that the F/C is actually performed in the engine 10 after the F/C command for suppressing backlash elimination shock is issued. This is because the time for approximately three ignitions is required.

In step S301, when it is determined that the gear becomes loose after three ignitions (step S301: Yes), the PCM 50 proceeds to step S302 and determines whether or not the F/C of the engine 10 may be executed. Specifically, the PCM 50 (i) is under load, in other words, the clutch 202 is engaged, (ii) the vehicle speed is equal to or higher than a predetermined speed (approximately 1 to 2 km/h), ( iii) that F/C has never been executed since the accelerator was turned on; and (iv) that the engine 10 is not in cylinder deactivation operation. judge. That is, the PCM 50 determines that F/C may be executed when all four conditions (i) to (iv) are satisfied, while the four conditions (i) to (iv) are 1. If none of the conditions are met, it is not determined that F/C may be executed. The condition (iii) that F/C has never been executed since the accelerator is turned on is used because the accelerator pedal is repeatedly depressed and released, and F/C is executed many times. This is to prevent shock from occurring.

When it is determined in step S302 that F/C may be executed (step S302: Yes), the PCM 50 proceeds to step S303 and executes F/C for one cylinder 11 of the engine 10. Specifically, the PCM 50 controls the fuel injection valve 13 so as to stop the supply of fuel to the cylinder 11 in which combustion occurs next among all the cylinders 11 . As a result, by temporarily reducing the torque of the engine 10 when the gear becomes loose, the looseness reduction shock is suppressed.

On the other hand, if it is not determined that the looseness of the gear is clogged after three ignitions (step S301: No) and if it is not determined that F/C may be executed (step S302: No), the PCM 50 Proceed to step S304. In this case, the PCM 50 does not execute F/C of the engine 10 (step S304).

After steps S303 and S304, the PCM 50 ends the loose F/C control and returns to the main routine (FIG. 5).

Next, with reference to FIG. 13, a specific description will be given of how to obtain the above-described backlash elimination time. FIG. 13 shows time charts of angular velocity (the solid line is the angular velocity of the wheel, the broken line is the angular velocity of the engine 10), the backlash angle, the backlash angular velocity, the backlash angular acceleration, and the torque of the engine 10, in order from the top.

In the example shown in FIG. 13, at time t21, the angular velocity of the engine 10 diverges from the angular velocity of the wheels (specifically, acceleration causes the angular velocity of the engine 10 to become greater than the angular velocity of the wheels). At this time t21, the looseness of the gear starts to be reduced. The PCM 50 obtains the looseness elimination time in the following procedure when the looseness elimination is started in this manner. The backlash angle is obtained by integrating the backlash speed, the backlash speed is obtained by integrating the backlash acceleration, and the backlash acceleration corresponds to the torque of the engine 10 and the running resistance. Therefore, the PCM 50 obtains the backlash acceleration from the torque of the engine 10 and the running resistance, and obtains the backlash speed from this backlash acceleration (the initial speed v21 is given to the backlash speed from the speed of the flywheel on the engine 10 side). , the backlash angle is obtained from this backlash speed. Then, the PCM 50 obtains the clearance reduction timing (time t22) of the gear from the obtained backlash angle and the backlash design value described above. The PCM 50 uses the time from time t21 to time t22 as the looseness elimination time. Then, when the looseness is eliminated (time t21), the PCM 50 sets a timer corresponding to this looseness elimination time and counts down.

Next, with reference to FIG. 14, the F/C command timing for suppressing backlash shock will be specifically described. FIG. 14 shows time charts of ignition timing, backlash elimination time (timer), F/C instruction timing, and F/C execution timing in order from the top.

As described above, it takes about three ignitions from when the F/C command is issued until the F/C is actually performed in the engine 10 . Therefore, when the timer corresponding to the backlash elimination time is set, the PCM 50 obtains the timing T31, which is equivalent to three ignitions before the timing at which the countdown of this timer ends (backlash elimination completion timing), and determines this timing. A F/C instruction for the engine 10 is issued when the temperature reaches . As a result, F/C is actually executed in the engine 10 at the timing of completion of the backlash elimination.

Next, with reference to FIG. 15, effects of backlash elimination F/C control according to the embodiment of the present invention will be described. FIG. 15 shows time charts of engine speed, accelerator opening, acceleration, actual torsion angle, estimated torsion angle, backlash reduction time (timer), and engine torque in order from the top. In FIG. 15, the solid line shows the results when the backlash elimination F/C control according to this embodiment is executed, and the dashed line shows the results when the backlash elimination F/C control according to this embodiment is not executed. showing. FIG. 15 illustrates the acceleration of vehicle 500 .

In this embodiment, the PCM 50 operates at the timing of completion of backlash elimination during acceleration, that is, at the timing when the countdown of the timer corresponding to the backlash elimination time ends (at this timing, the torsion angle of the drive shaft 209 changes from 0 toward the driving direction). change), F/C for one cylinder 11 of the engine 10 is executed by backlash reduction F/C control (see arrow A21). By executing such backlash-removing F/C control, the vibration of the vehicle body (backlash-removing shock) after completion of backlash elimination is appropriately suppressed compared to the case where the backlash-removal F/C control is not executed ( See arrow A22).

It should be noted that the reason why F/C is performed only for one cylinder 11 in the backlash reduction F/C control is from the viewpoint of ensuring emissions. However, when the emissions do not deteriorate even if F/C is executed for two or more cylinders 11, or when priority is given to suppressing backlash shocks (vibration damping properties) over emissions, the backlash elimination F/C control F/C for two or more cylinders 11 may be executed.

(Torque F/C control)
Next, the torque F/C control performed in step S111 of FIG. 5 will be specifically described. As described above, PCM 50 executes torque F/C control for stopping (F/C) supplying fuel to engine 10 when vehicle 500 decelerates.

FIG. 16 is a flow chart showing torque F/C control according to an embodiment of the present invention. Basically, this torque F/C control is executed when vehicle 500 decelerates.

When torque F/C control is started, first, in step S401, the PCM 50 determines whether or not torque F/C control execution conditions are satisfied. Specifically, the PCM 50 determines that (i) the accelerator opening has decreased from a predetermined opening or more to a predetermined speed or more, and (ii) a condition for prohibiting torque F/C control has not been established. Specifically, the F/C is not operated by another control (such as the above-mentioned backlash reduction F/C control), (iii) the engine speed is a predetermined value or more and the gear is a predetermined value or more. (iv) being in the F/C permission zone; (v) satisfying the conditions related to engine charging efficiency; Judgment is performed using the following five conditions. That is, the PCM 50 determines that the torque F/C control execution condition is satisfied when all of the five conditions (i) to (v) are satisfied. If even one of the five conditions is not satisfied, it is not determined that the torque F/C control execution condition is satisfied.

If it is determined in step S401 that the torque F/C control execution condition is satisfied (step S401: Yes), the PCM 50 proceeds to step S402 and executes F/C among all the cylinders 11 of the engine 10. The number of cylinders (number of F/C cylinders) to be used is obtained. Specifically, the PCM 50 is a ratio of target torque (target Torque/retard limit torque) is obtained, and based on this ratio, the number of cylinders capable of achieving the target torque is obtained. A value obtained by subtracting this feasible number of cylinders from the total number of cylinders is the number of F/C cylinders. The formula for obtaining the number of F/C cylinders is expressed by "number of F/C cylinders=total number of cylinders-{(target torque/retard limit torque)×total number of cylinders}". Basically, since the vehicle 500 is decelerating, there is a tendency that "target torque < retard limit torque", that is, the ratio of "target torque/retard limit torque" tends to be less than 1 (less than 100%). It is in.

Next, at step S403, the PCM 50 increases the number of F/C cylinders when the driver's request for deceleration increases after step S402. The PCM 50 maintains the F/C cylinder number if the deceleration request has not changed. Then, the PCM 50 proceeds to step S404 and controls the engine 10 according to the number of F/C cylinders obtained in this way. Specifically, the PCM 50 controls the fuel injection valves 13 to stop the supply of fuel to the cylinders 11 corresponding to the number of F/C cylinders among all the cylinders 11 .

On the other hand, if it is not determined that the torque F/C control execution condition is satisfied (step S401: No), the PCM 50 proceeds to step S405. In this case, the PCM 50 does not execute F/C of the engine 10 (step S405). The PCM 50 sets the number of F/C cylinders to 0 so that in step S404 the engine 10 is controlled normally without F/C.

After step S404, the PCM 50 ends torque F/C control and returns to the main routine (FIG. 5).

(backlash twist control)
Next, the backlash twist control performed in step S112 of FIG. 5 will be specifically described. As this backlash torsion control, the PCM 50 controls the vehicle body vibration caused by the torsion of the drive shaft 209 and the vehicle body vibration (backlash reduction shock) that occurs when the gears become loose when the vehicle 500 decelerates. F/C for 10 will be executed.

17 to 21, rattle twist control according to an embodiment of the present invention will be described. FIG. 17 is a flow chart showing rattle twist control according to the embodiment of the present invention, FIG. 18 is a time chart showing the first control of rattle twist control according to the embodiment of the present invention, and FIG. FIG. 20 is a time chart showing the second rattling twist control according to the embodiment, FIG. 20 is a time chart showing the third rattling twist control according to the embodiment of the present invention, and FIG. 4 is a time chart showing fourth control of backlash twist control by .

Here, in describing backlash control, a case where the total number of cylinders of the engine 10 is 4, that is, a case where the engine 10 is a 4-cylinder engine will be taken as an example. However, it is needless to say that the application of the rattle twist control according to this embodiment is not limited to a four-cylinder engine, in other words, the application of the rattle twist control according to this embodiment can also be applied to other multi-cylinder engines.

The backlash torsion control in FIG. 17 is basically executed when vehicle 500 is decelerating. When this backlash torsion control is started, first, in step S501, the PCM 50 determines whether or not the backlash of the gears is clogged after three ignitions of the engine 10 based on the result of the above-described backlash-torsion state quantity estimation processing. . In this case as well, similar to the backlash elimination F/C control (see step S301 in FIG. 12), determination may be made using the backlash elimination time.

If it is determined in step S501 that the backlash is not eliminated after three ignitions (step S501: No), the PCM 50 ends the backlash twist control and returns to the main routine (FIG. 5). On the other hand, if it is determined that the looseness is clogged after three ignitions (step S501: Yes), the PCM 50 proceeds to step S502 to check whether the number of F/C cylinders is the total number of cylinders (4 cylinders). judge. That is, the PCM 50 determines whether or not all cylinders 11 have been set as targets for F/C by the torque F/C control described above. The determination in step S502 corresponds to determining whether or not the driver's deceleration request is very large.

When it is determined in step S502 that the number of F/C cylinders is the total number of cylinders (step S502: Yes), the PCM 50 proceeds to step S503. In this case, the PCM 50 executes the first control of backlash twist control in steps S503 and S504. Here, the first control will be specifically described with reference to FIG. 18 . This first control is executed when the driver's deceleration request is very large.

FIG. 18 shows the twist angle of the drive shaft 209 at the top and the number of F/C cylinders at the bottom. Here, it is assumed that the vehicle 500 is decelerating due to the accelerator being turned off, and F/C is being performed for all cylinders 11 (four cylinders). In this case, the torsion angle of drive shaft 209 decreases to 0 (time t41), and after a lapse of time T41, the torsion angle of drive shaft 209 begins to change in the deceleration direction (time t42). The period from time t41 to time t42 corresponds to the period from the start of gear elimination to the completion of elimination of backlash. After time t42, the drive shaft 209 undergoes a periodic torsion according to its natural frequency due to running resistance.

In the first control, the PCM 50 gradually restores the F/C in step S503 when the torsion angle of the drive shaft 209 changes from 0 toward the deceleration direction (time t42). Specifically, the PCM 50 gradually restarts the fuel supply to the cylinders 11 to which the fuel supply has been stopped, that is, sequentially restarts the fuel supply to each cylinder, thereby increasing the torque of the engine 10 . As a result, the vibration (backlash reduction shock) that occurs when the backlash is completely eliminated is suppressed.

After that, in step S504, when the torsion angle of the drive shaft 209 reaches the first peak in the deceleration direction (hereinafter referred to as "deceleration peak") (time t43), the PCM 50 controls the F/C gradually resume. Specifically, when 1/4 of the period corresponding to the natural frequency of the drive shaft 209 has elapsed from time t42, the PCM 50 gradually restarts the fuel supply to the cylinder 11 to which the fuel supply was restarted. The torque of the engine 10 is reduced by stopping, that is, by sequentially restarting the F/C for each cylinder. This suppresses the twisting of the drive shaft 209 after the deceleration peak, thereby suppressing the vibration caused by the torsion of the drive shaft 209 . According to such first control, it is possible to appropriately suppress both the vibration that occurs when the backlash is reduced (backlash reduction shock) and the vibration that is caused by the torsion of the drive shaft 209 .

Returning to FIG. 17, in step S502, if it is not determined that the number of F/C cylinders is the total number of cylinders (step S502: No), the PCM 50 proceeds to step S505, and after three ignitions, the twisting of the drive shaft 209 is detected. is a peak (deceleration peak). The PCM 50 obtains the timing at which the torsion peaks from the 1/4 time of the cycle corresponding to the natural frequency of the drive shaft 209, obtains the timing corresponding to three ignitions before this timing, and performs step S505. make a judgment.

If it is not determined in step S505 that the twist will reach its peak after three ignitions (step S505: No), the PCM 50 terminates rattle twist control and returns to the main routine (FIG. 5). On the other hand, if it is determined that the twist peaks after three ignitions (step S505: Yes), the PCM 50 proceeds to step S506 to determine whether the driver's deceleration request is relatively large. Specifically, the PCM 50 determines whether or not the driver's deceleration request is relatively large, based on at least one or more of the gear position, engine speed, and engine torque. It is assumed that the level of the deceleration request determined in step S506 is lower than the level of the deceleration request required when the first control described above is executed. For example, the PCM 50 determines in step S506 that the deceleration request is relatively large when the gear stage is 3rd or higher, the engine speed is 3000 rpm or higher, and the engine torque is 150 Nm or higher.

If it is determined in step S506 that the deceleration request is relatively large (step S506: Yes), the PCM 50 proceeds to step S507. In this case, the PCM 50 executes the second backlash control in step S507. Here, the second control will be specifically described with reference to FIG. 19 .

FIG. 19 shows the twist angle of the drive shaft 209 at the top and the number of F/C cylinders at the bottom. Here, it is assumed that the vehicle 500 is decelerating, but the F/C is not yet executed (the number of F/C cylinders=0). The change in the torsion angle of the drive shaft 209 shown in FIG. 19 is the same as in FIG. 18, so the description thereof will be omitted.

In the second control, the PCM 50 executes F/C for all cylinders 11 in step S507 when the twist angle of the drive shaft 209 reaches the first deceleration peak (time t43). Specifically, the PCM 50 reduces the torque of the engine 10 by stopping the fuel supply to all cylinders 11 by stopping the fuel supply to the cylinders one by one. This suppresses the twisting of the drive shaft 209 after the deceleration peak, thereby suppressing the vibration caused by the torsion of the drive shaft 209 . According to such second control, it is possible to appropriately suppress the vibration caused by the torsion of the drive shaft 209 while surely satisfying the deceleration request.

Returning to FIG. 17, if it is not determined in step S506 that the deceleration request is relatively large (step S506: No), the PCM 50 proceeds to step S508 to determine whether the driver's deceleration request is moderate. judge. Specifically, the PCM 50 determines whether or not the driver's request for deceleration is moderate based on at least one or more of the gear position, engine speed, and engine torque. Assume that the level of the deceleration request determined in step S508 is lower than the level of the deceleration request determined in step S506. For example, when the engine speed is 1500 rpm or more and the engine torque is 50 Nm or more, the PCM 50 determines that the deceleration request is moderate in step S508.

If it is determined in step S508 that the deceleration request is moderate (step S508: Yes), the PCM 50 proceeds to step S509. In this case, the PCM 50 executes the third backlash twist control in steps S509 and S510. Here, with reference to FIG. 20, the third control will be specifically described.

FIG. 20 shows the twist angle of the drive shaft 209 at the top and the number of F/C cylinders at the bottom. Here, it is assumed that the vehicle 500 is decelerating, but the F/C is not yet executed (the number of F/C cylinders=0). The change in the torsion angle of the drive shaft 209 shown in FIG. 20 is the same as in FIG. 18, so the description thereof will be omitted.

In the third control, in step S509, when the torsion angle of drive shaft 209 reaches the first deceleration peak (time t43), PCM 50 executes F/C for two cylinders 11 among the four cylinders. Specifically, the PCM 50 stops the fuel supply to the two cylinders 11 one by one in order, thereby reducing the torque of the engine 10 . Thereafter, in step S510, the PCM 50 executes F/C for two more cylinders 11 when the twist angle of the drive shaft 209 reaches the second deceleration peak (time t44). Specifically, the PCM 50 stops the fuel supply to the cylinders one by one in order, and stops the fuel supply to the remaining two cylinders 11 to reduce the torque of the engine 10 . As a result, F/C for all cylinders 11 is completed. In such a third control, the vibration caused by the torsion of the drive shaft 209 is suppressed by suppressing the torsion of the drive shaft 209 after each of the first and second deceleration peaks. As a result, it is possible to effectively suppress the vibration caused by the torsion of the drive shaft 209 while satisfying the deceleration request to some extent.

Returning to FIG. 17, if it is not determined in step S508 that the deceleration request is moderate (step S508: No), that is, if the deceleration request is low, the PCM 50 proceeds to step S511. In this case, the PCM 50 executes the fourth backlash twist control in steps S511 to S514. Here, the fourth control will be specifically described with reference to FIG. 21 .

FIG. 21 shows the twist angle of the drive shaft 209 at the top and the number of F/C cylinders at the bottom. Here, it is assumed that the vehicle 500 is decelerating, but the F/C is not yet executed (the number of F/C cylinders=0). The change in the torsion angle of the drive shaft 209 shown in FIG. 21 is the same as in FIG. 18, so the description thereof will be omitted.

In the fourth control, in step S511, when the twist angle of the drive shaft 209 reaches the first deceleration peak (time t43), the PCM 50 executes F/C for one cylinder 11 out of the four cylinders. (The number of F/C cylinders becomes 1), and the torque of the engine 10 is reduced. Next, in step S512, when the twist angle of the drive shaft 209 reaches the second deceleration peak (time t44), the PCM 50 further executes F/C for one cylinder 11 (F/C cylinder number = 2), reducing the torque of the engine 10 . Next, in step S513, when the twist angle of the drive shaft 209 reaches the third deceleration peak (time t45), the PCM 50 further executes F/C for one cylinder 11 (F/C cylinder number = 3), reducing the torque of the engine 10 . Next, in step S514, when the twist angle of the drive shaft 209 reaches the fourth deceleration peak (time t46), the PCM 50 further executes F/C for one cylinder 11 (F/C cylinder number = 4), reducing the torque of the engine 10 . As a result, F/C for all cylinders 11 is completed. In such fourth control, the vibration caused by the torsion of the drive shaft 209 is suppressed by suppressing the torsion of the drive shaft 209 after each of the first to fourth deceleration peaks. As a result, vibration caused by torsion of the drive shaft 209 can be suppressed more effectively.

After steps S504, S507, S510, and S514, the PCM 50 terminates backlash twist control and returns to the main routine (FIG. 5).

<Effect>
Next, the effects of the vehicle control device according to the embodiment of the present invention will be described.

In the present embodiment, the PCM 50 reduces the torque of the engine 10 when the accelerator opening is almost 0 (opening corresponding to accelerator off), and then the difference between the angular velocity on the engine 10 side and the angular velocity on the wheel side is reduced. Based on this, the actual torsion angle of the drive shaft 209 is determined, and the torque is increased when the actual torsion angle changes from 0 toward the deceleration direction. When the actual torsional angle changes from 0 to the deceleration direction, the gears in the power transmission system 207 become loose. It is possible to appropriately suppress the vehicle body vibration (backlash reduction shock) that occurs when the

Further, in the present embodiment, the PCM 50 reduces the torque of the engine 10 again when the actual torsion angle reaches the peak in the deceleration direction (deceleration peak) after increasing the torque of the engine 10 . As a result, it is possible to suppress the torsion of the drive shaft 209 after the deceleration peak, and to appropriately suppress the vibration caused by the torsion of the drive shaft 209 .

Further, in this embodiment, when the PCM 50 determines that the deceleration request is relatively large, the torque is reduced when the accelerator opening becomes approximately 0, and then the actual torsion angle increases from 0 toward the deceleration direction. while increasing the torque when it changes to , if it is determined that the deceleration request is relatively small, the actual torsion angle will be in the deceleration direction without decreasing the torque when the accelerator opening becomes almost 0 Decrease the torque when the side peak is reached. As a result, when the deceleration request is relatively large, the vehicle body vibration can be suppressed while the deceleration request is reliably satisfied. can be effectively suppressed. Incidentally, whether the deceleration request is relatively large or relatively small may be determined using the torque F/C control execution conditions described above (see step S401 in FIG. 16). In one example, the condition that "(i) the accelerator opening is decreased at a predetermined speed or more from a predetermined opening or more" in the torque F/C control execution conditions may be used.

Further, in this embodiment, when the PCM 50 determines that the deceleration request is relatively small, the PCM 50 further determines the degree of the deceleration request based on at least one of the angular velocity, torque, and gear stage of the engine 10 side. , the torque reduction method is changed according to the degree of the deceleration request. As a result, it is possible to flexibly change whether to give priority to the deceleration request or to give priority to vibration suppression.

Further, in this embodiment, the PCM 50 has a torque reduction method for executing F/C for all cylinders 11 when the actual torsion angle reaches the first deceleration peak, and an actual torsion The torque reduction method is switched between sequentially executing F/C for each cylinder 11 every time the angle reaches a plurality of temporally continuous deceleration peaks. According to the former method, it is possible to satisfy the deceleration request with priority over the latter method. can be effectively suppressed.

Further, in this embodiment, the PCM 50 executes F/C when the accelerator opening becomes approximately 0, and then executes F/C when the actual torsion angle changes from 0 toward the deceleration direction. Since the fuel supply to the cylinder 11 that has been stopped is resumed, the torque of the engine 10 can be appropriately increased to reliably suppress backlash-filling shock.

Further, in this embodiment, when the actual torsion angle reaches the deceleration peak, the PCM 50 resumes F/C for the cylinder 11 to which the fuel supply has been resumed. Vibration caused by torsion of the shaft 209 can be reliably suppressed.

Further, in this embodiment, the PCM 50 obtains the angular velocity on the engine 10 side based on the torque of the engine 10 and also obtains the angular velocity on the wheel side based on the running resistance of the vehicle 500, so that the actual torsion angle can be obtained with high accuracy. .

Further, in this embodiment, the PCM 50 determines the actual torsion angle based on the angular velocity on the engine 10 side and the angular velocity on the wheel side, based on the rotation speed of the transmission 204 (the rotation speed of the clutch 202 (the rotation speed of the P-axis)). Since the angular velocity on the engine 10 side is corrected, the actual torsion angle can be obtained with higher accuracy.

Further, in this embodiment, the PCM 50 sets the target torsion angle of the drive shaft 209 based on the target acceleration corresponding to the accelerator opening, sets the target torque of the engine 10 based on this target torsion, and controls the engine 10. . As a result, it is possible to apply a target torque that takes into consideration the behavior of the drive shaft 209 during acceleration and deceleration (that is, during a transition of torque increase or torque decrease), thereby suppressing vehicle body vibration caused by torsion of the drive shaft 209. , it is possible to ensure responsiveness (transient responsiveness) during acceleration and deceleration.

In this embodiment, the PCM 50 sets the target torque based on the torsion angular torque corresponding to the torsion angle of the drive shaft 209 and the torsion angular velocity torque corresponding to the torsion angular velocity of the drive shaft 209. It is possible to apply a target torque with appropriate consideration of behavior. By applying such a target torque, an actual torsion angle corresponding to the target torsion angle can be generated appropriately, and vibration caused by torsion of the drive shaft 209 can be effectively suppressed.

Further, in the present embodiment, the target torque has a time waveform that increases according to the torsional angular torque and temporarily decreases according to the torsional angular velocity torque during this rising process. It is possible to apply a target torque that more effectively takes into account the behavior of the drive shaft 209 during the transition of the decrease.

Further, in this embodiment, the PCM 50 corrects the target torque based on the difference between the target torsion angle set as described above and the actual torsion angle of the drive shaft 209. to be realized.

<Modification>
In the above-described embodiment, an example in which the present invention is applied to a vehicle 500 having an engine 10 as a driving source has been shown. (EV vehicle)) may be applied to the present invention. In vehicle 501, motor 300 is connected to reduction gear 205 via clutch 202 (the rest of the configuration is similar to vehicle 500). In such a modification, the PCM 50 (controller) (not shown) may adjust the torque of the motor 300 by controlling the motor 300 via an inverter (not shown). In a further modified example, the present invention may be applied to a vehicle having an engine and a motor as drive sources (so-called hybrid vehicle).

5 throttle valve 10 engine 11 cylinder 13 fuel injection valve 14 spark plug 30 accelerator opening sensor 50 PCM
100 engine system 202 clutch 204 transmission 207 power transmission system 209 drive shaft 300 motor 500, 501 vehicle

Claims (13)

A control device for a vehicle,
an accelerator opening sensor that detects the accelerator opening;
a torque adjustment mechanism that adjusts the torque of the drive source of the vehicle;
a controller that controls the torque adjustment mechanism based on the accelerator opening detected by the accelerator opening sensor;
The controller is
controlling the torque adjustment mechanism to reduce the torque of the drive source when the accelerator opening becomes substantially zero;
Thereafter, based on the difference between the angular velocity on the drive source side and the angular velocity on the wheel side of the vehicle, the actual torsional angle of the drive shaft for driving the wheels is obtained, and the actual torsional angle increases from 0 to the decelerating direction of the wheels. is configured to control the torque adjustment mechanism to increase the torque of the drive source when the
The controller controls the torque adjustment mechanism to decrease the torque of the drive source again when the actual torsion angle reaches a peak in the deceleration direction after increasing the torque of the drive source. configured as
A vehicle control device characterized by: A control device for a vehicle,
an accelerator opening sensor that detects the accelerator opening;
a torque adjustment mechanism that adjusts the torque of the drive source of the vehicle;
a controller that controls the torque adjustment mechanism based on the accelerator opening detected by the accelerator opening sensor;
When the accelerator opening becomes approximately 0, the controller
When it is determined that the driver's deceleration request is large, after reducing the torque of the drive source , the wheels are driven based on the difference between the angular velocity on the drive source side and the angular velocity on the wheel side of the vehicle. while controlling the torque adjustment mechanism to increase the torque of the drive source when the actual torsion angle of the drive shaft changes from 0 to the deceleration direction,
When it is determined that the deceleration request is small, the torque adjustment mechanism is controlled to reduce the torque of the drive source when the actual torsion angle reaches a peak in the deceleration direction. ,
A vehicle control device characterized by : When the controller determines that the deceleration request is small, the controller determines the extent of the deceleration request based on at least one of the angular velocity of the drive source, the torque of the drive source, and the gear stage of the transmission of the vehicle. is further determined, and the method of reducing the torque of the drive source when the actual torsion angle reaches the peak in the deceleration direction is changed according to the degree of the deceleration request. Item 3. The vehicle control device according to item 2. The drive source includes an engine having multiple cylinders,
The torque adjustment mechanism includes a fuel adjustment device that adjusts fuel supply to each cylinder of the engine,
The controller adjusts the fuel so as to stop fuel supply to all cylinders of the engine when the actual torsion angle reaches a first peak in the deceleration direction according to the degree of the deceleration request. A method of reducing the torque of the drive source by controlling a device, and supplying fuel to each cylinder of the engine each time the actual torsion angle reaches a plurality of temporally continuous peaks in the deceleration direction. and a method of reducing the torque of the drive source by controlling the fuel adjustment device to stop in sequence,
The control device for a vehicle according to claim 3 . The drive source includes an engine having multiple cylinders,
The torque adjustment mechanism includes a fuel adjustment device that adjusts fuel supply to each cylinder of the engine,
The controller is
reducing the torque of the engine by controlling the fuel adjustment device to stop fuel supply to the cylinder of the engine when the accelerator opening becomes substantially zero;
After that, when the actual torsion angle changes from 0 to the deceleration direction, the engine torque is increased by controlling the fuel adjustment device so as to restart the fuel supply to the cylinders to which the fuel supply has been stopped. configured to raise
The vehicle control device according to any one of claims 1 to 4 . After increasing the torque of the engine, when the actual torsion angle reaches a peak in the deceleration direction, the controller controls the fuel supply so as to stop the fuel supply again to the cylinder to which the fuel supply has been restarted. 6. A control device for a vehicle as claimed in claim 5 , arranged to control the regulating device. The controller determines the angular velocity of the drive source based on the torque from the drive source, determines the angular velocity of the wheel based on the running resistance of the vehicle, and determines the actual torsion angle based on the difference between these angular velocities. The vehicle control device according to any one of claims 1 to 6 , wherein the vehicle control device is configured to: 8. The vehicle control device according to claim 7 , wherein the controller is configured to correct the angular velocity of the drive source based on the rotation speed of the transmission of the vehicle. The controller is
setting a target acceleration of the vehicle based on the accelerator opening;
setting a target torsion angle of the drive shaft based on the target acceleration;
setting a target torque of the drive source based on the target twist angle ;
configured to control the torque adjustment mechanism based on the target torque,
The vehicle control device according to any one of claims 1 to 8 . The controller sets the target torque based on a first torque corresponding to the torsional angle of the drive shaft and a second torque corresponding to the torsional angular velocity of the drive shaft in order to achieve the target torsional angle. 10. The control device for a vehicle according to claim 9 , configured as follows. 11. The vehicle control device according to claim 10 , wherein said target torque has a time waveform such that said target torque increases according to said first torque and temporarily decreases according to said second torque during this increasing process. The vehicle control device according to any one of claims 9 to 11 , wherein said controller is configured to correct said target torque based on a difference between said target torsion angle and said actual torsion angle. . The vehicle control device according to any one of claims 1 to 12 , wherein the drive source includes an engine or a motor.

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