JP6725255B2 - Vehicle control device and vehicle control method - Google Patents

Description

The present invention relates to a vehicle control device and a vehicle control method.

When a predetermined condition is satisfied, a control device for a vehicle that executes a so-called sailing stop control, in which a clutch is released to bring an automatic transmission into a neutral state (power cutoff state) and a drive source is stopped to travel, is disclosed in Patent Document 1. It is disclosed.

JP, 2013-213557, A

If the vehicle speed becomes lower than the predetermined vehicle speed during the sailing stop control, cancel the sailing stop control and transmit the rotation of the drive wheels to the driven machine such as the alternator or oil pump to promptly operate the driven machine. Is desirable.

Such a request is made not only when the sailing stop control is released but also when the vehicle speed becomes lower than the predetermined vehicle speed during the neutral travel control in which the clutch is released during traveling and the automatic transmission is in neutral. Also occurs.

The present invention has been invented to solve such a problem, and an object of the present invention is to quickly operate a driven machine when the vehicle speed becomes lower than a predetermined vehicle speed during execution of neutral travel control. ..

A control device for a vehicle according to an aspect of the present invention includes a drive source, a driven machine driven by the drive source, a power transmission path, which is provided downstream of the drive source and the driven machine, and locks up. A control device for a vehicle, comprising: a torque converter having a clutch; and an automatic transmission having a fastening element provided on a downstream side of the torque converter in a power transmission path. When the vehicle speed becomes lower than the predetermined vehicle speed during the neutral traveling control in the cut-off state, the control unit includes a control unit that engages the engagement element with the lock-up clutch engaged, and the control unit has the vehicle speed equal to or higher than the predetermined vehicle speed. in the state, the predetermined neutral travel control release conditions other than when the vehicle speed becomes less than the predetermined vehicle speed is when a condition is satisfied, for fastening the fastening element in a state that releases the lockup clutch.

According to another aspect of the present invention, there is provided a vehicle control method, a drive source, a driven machine driven by the drive source, a power transmission path, which is provided on a downstream side of the drive source and the driven machine. a torque converter with a up clutch, the power transmission path, a control method for a vehicle for controlling a vehicle having an automatic transmission having a fastening element which is provided downstream of the torque converter, while the vehicle is traveling When the vehicle speed becomes lower than the predetermined vehicle speed during the neutral traveling control in which the automatic transmission is in the power-off state, the engagement element is engaged with the lockup clutch engaged, and the vehicle speed is equal to or higher than the predetermined vehicle speed. If the predetermined neutral travel control release conditions other than when the vehicle speed becomes less than the predetermined vehicle speed is established, to enter into engagement element in a state that releases the lockup clutch.

According to these aspects, when the vehicle speed becomes lower than the predetermined vehicle speed during the neutral traveling control, the fastening element is fastened by fastening the lock-up clutch, so that the driven machine is promptly fastened after fastening the fastening element. Can be operated. When the vehicle speed is equal to or higher than the predetermined vehicle speed during the neutral travel control and the predetermined neutral travel control release condition is satisfied except when the vehicle speed is lower than the predetermined vehicle speed, the lockup clutch is disengaged. By fastening the elements, it is possible to suppress the occurrence of fastening shock of the fastening elements.

It is a schematic block diagram of the vehicle of this embodiment. It is a flowchart when canceling the sailing stop control in the present embodiment. 8 is a time chart when canceling the sailing stop control in the comparative example. 8 is a time chart when canceling the sailing stop control in the comparative example. 6 is a time chart when canceling the sailing stop control in the present embodiment.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. In the following, the gear ratio is a value obtained by dividing the rotation speed of the input shaft of the continuously variable transmission by the rotation speed of the output shaft of the continuously variable transmission.

FIG. 1 is a schematic configuration diagram of a vehicle of this embodiment. The vehicle includes an engine 1, a torque converter 2, a forward/reverse switching mechanism 3, a continuously variable transmission (variator) 4, a hydraulic control circuit 5, a mechanical oil pump 6m, an electric oil pump 6e, and an alternator 7. An engine controller 10 and a transmission controller 11 are provided.

In the vehicle, the rotation generated by the engine 1 is transmitted to a drive wheel (not shown) via the torque converter 2, the forward/reverse switching mechanism 3, the continuously variable transmission 4, the gear set 8, and the differential gear device 9. That is, the rotation of the engine 1 is transmitted from the upstream side to the downstream side in the power transmission path in which the engine 1 side is upstream and the drive wheel side is downstream. The torque converter 2, the forward/reverse switching mechanism 3, and the continuously variable transmission 4 constitute an automatic transmission 15.

The torque converter 2 has a lockup clutch 2a. When the lockup clutch 2a is engaged, the input shaft and the output shaft of the torque converter 2 are directly connected, and the input shaft and the output shaft rotate at the same speed. ..

The forward/reverse switching mechanism 3 has a double pinion planetary gear set as a main component, and its sun gear is connected to the engine 1 via the torque converter 2 and the carrier is connected to the primary pulley 4a. The forward/reverse switching mechanism 3 further includes a forward clutch 3a that directly connects the sun gear of the double pinion planetary gear set and the carrier, and a reverse brake 3b that fixes the ring gear. When the forward clutch 3a is engaged, the engine 1 passes through the torque converter 2. The input rotation is transmitted to the primary pulley 4a as it is, and when the reverse brake 3b is engaged, the input rotation from the engine 1 via the torque converter 2 is transmitted to the primary pulley 4a under deceleration in the reverse rotation.

The states of the forward clutch 3a and the reverse brake 3b include "released", "standby", "slip", and "engaged" states. These states are switched according to the hydraulic pressure supplied to each piston pressure receiving chamber.

"Release" is a state in which, for example, the hydraulic pressure is not supplied to the forward clutch 3a and the forward clutch 3a has no torque capacity.

The "standby" is a state in which the forward clutch 3a does not have a torque capacity although the forward clutch 3a is supplied with hydraulic pressure, for example. In the "standby" state, the forward clutch 3a is in a state immediately before having a torque capacity.

"Slip" means, for example, a forward/reverse switching mechanism when hydraulic pressure is supplied to the forward clutch 3a, the forward clutch 3a has a torque capacity, and the forward clutch 3a is engaged between the input/output shafts of the forward/reverse switching mechanism 3. This is a state in which a rotational speed difference taking into consideration the gear ratio R1 of 3 has occurred. In the "slip" state, the torque capacity is smaller than the input torque of the forward clutch 3a.

The "engagement" is, for example, a forward/reverse switching mechanism when hydraulic pressure is supplied to the forward clutch 3a, the forward clutch 3a has a torque capacity, and the forward clutch 3a is fastened between the input/output shafts of the forward/reverse switching mechanism 3. This is a state in which a rotational speed difference taking into consideration the gear ratio R1 of 3 has not occurred. In the “engaged” state, the torque capacity is larger than the input torque of the forward clutch 3a. The "engaged" state includes complete engagement in which the torque capacity is further increased after the torque capacity becomes larger than the input torque of the forward clutch 3a, and the torque capacity has a margin for the input torque.

The continuously variable transmission 4 includes a primary pulley 4a, a secondary pulley 4b, and a belt 4c. In the continuously variable transmission 4, by controlling the hydraulic pressure supplied to the primary pulley 4a and the hydraulic pressure supplied to the secondary pulley 4b, the contact radius between each pulley 4a, 4b and the belt 4c is changed, and The gear ratio of the stage transmission 4 is changed.

The mechanical oil pump 6m is a mechanical oil pump that is driven by the rotation of the output shaft of the engine 1. That is, the mechanical oil pump 6m is a driven machine. By the drive of the mechanical oil pump 6m, the oil discharged from the mechanical oil pump 6m is supplied to the hydraulic control circuit 5. When the engine 1 is stopped, the mechanical oil pump 6m is not driven and oil is not discharged from the mechanical oil pump 6m.

The electric oil pump 6e is an electric oil pump that is driven by electric power supplied from a battery. By driving the electric oil pump 6e when the mechanical oil pump 6m is not driven, oil can be supplied to the hydraulic control circuit 5 even when the engine is stopped.

The alternator 7 is driven by the rotation of the output shaft of the engine 1. That is, the alternator 7 is a driven machine.

The hydraulic control circuit 5 includes a plurality of flow paths and a plurality of hydraulic actuators. The hydraulic actuator is composed of a solenoid and a hydraulic control valve. In the hydraulic control circuit 5, the hydraulic actuator is controlled based on the control signal from the transmission controller 11, the hydraulic pressure supply path is switched, and the line pressure generated by the oil discharged from the mechanical oil pump 6m and the electric oil pump 6e is controlled. The required hydraulic pressure is adjusted from. The hydraulic control circuit 5 supplies the adjusted hydraulic pressure to each part of the continuously variable transmission 4, the forward/reverse switching mechanism 3, and the torque converter 2.

The transmission controller 11 is composed of a CPU, a ROM, a RAM and the like. In the transmission controller 11, the function of the transmission controller 11 is exhibited by the CPU reading and executing the program stored in the ROM. The engine controller 10 is also composed of a CPU, ROM, RAM and the like.

The transmission controller 11 detects a signal from the accelerator pedal opening sensor 21 that detects the accelerator pedal opening APO corresponding to the operation amount of the accelerator pedal 41, and a brake fluid pressure BRP corresponding to the operation amount of the brake pedal 42. A signal from the brake fluid pressure sensor 22 and a signal from the inhibitor switch 23 that detects the position of the shift lever 40 are input. Further, the transmission controller 11 informs the transmission controller 11 of a signal from an engine rotation speed sensor 24 that detects an engine rotation speed Ne, which is a rotation speed of an output shaft of the engine 1, a rotation speed of a primary pulley 4a of the continuously variable transmission 4 (forward/backward movement). A signal from a primary rotation speed sensor 25 that detects a primary rotation speed Npri, which is the rotation speed on the output side of the switching mechanism 3, a signal from a vehicle speed sensor 26 that detects a vehicle speed VSP, and an engine controller 10 that controls the engine 1. A signal relating to the engine torque Te of is input.

In the present embodiment, when the sailing stop condition is satisfied while the vehicle is traveling, fuel injection into the engine 1 is stopped to stop the engine 1, and the forward/reverse switching mechanism 3 releases the forward clutch 3a and the reverse brake 3b. The sailing stop control is performed to set the neutral state. During the sailing stop control, the lockup clutch 2a is released.

As a result, the coasting distance becomes longer with the engine 1 stopped, and the fuel efficiency of the engine 1 can be improved.

The sailing stop conditions are, for example, the following conditions.

(A) The shift lever 40 is in the D range.
(B) The vehicle speed VSP is equal to or higher than the first predetermined vehicle speed (predetermined vehicle speed) V1.
(C) The accelerator pedal 41 is not depressed.
(D) The brake pedal 42 is not depressed.

The first predetermined vehicle speed V1 is medium or high vehicle speed and is set in advance.

The sailing stop condition is satisfied when all of the conditions (a) to (d) are satisfied, and is not satisfied when any of the conditions (a) to (d) is not satisfied.

When the sailing stop condition is not satisfied during the sailing stop control, the sailing stop control is released, the engine 1 is started, and the forward clutch 3a is engaged. That is, the sailing stop condition is also a sailing stop cancellation condition for canceling the sailing stop control. The sailing stop condition and the sailing stop cancellation condition may be different conditions.

When the sailing stop cancellation condition is satisfied, the engine 1 is started, and after the sailing stop cancellation control for engaging the forward clutch 3a is executed, normal traveling control is executed. In the sailing stop release control, the engagement control for engaging the forward clutch 3a is executed after the rotation synchronization control for starting the engine 1 and synchronizing the rotation speeds around the forward clutch 3a is executed. Sailing stop control, sailing stop release control (rotation synchronization control, engagement control), etc. are executed by the transmission controller 11 and the engine controller 10.

During the sailing stop control, the forward/reverse switching mechanism 3 is in the power cutoff state, and the automatic transmission 15 is in the neutral state. Further, since the engine 1 is stopped, the mechanical oil pump 6m is not driven. Therefore, during the sailing stop control, the required hydraulic pressure is supplied to the vehicle using the oil discharged from the electric oil pump 6e.

Next, the case of canceling the sailing stop control will be described with reference to the flowchart of FIG. Here, it is assumed that the sailing stop control is being executed.

In step S100, the transmission controller 11 determines whether or not the sailing stop cancellation condition (SS cancellation condition) is satisfied. Specifically, the transmission controller 11 determines whether or not any of the above (a) to (d) is no longer satisfied. If the sailing stop cancel condition is satisfied, the process proceeds to step S101, and if the sailing stop cancel condition is not satisfied, the process this time ends.

In step S101, the transmission controller 11 determines whether the vehicle speed VSP is less than the first predetermined vehicle speed V1. The vehicle speed VSP is detected based on the signal from the vehicle speed sensor 26. If the vehicle speed VSP is less than the first predetermined vehicle speed V1, the process proceeds to step S102. On the other hand, if the vehicle speed VSP is equal to or higher than the first predetermined vehicle speed V1, the process proceeds to step S106.

In step S102, the transmission controller 11 and the engine controller 10 execute sailing stop release control. Specifically, the transmission controller 11 engages the lockup clutch 2a, and the engine controller 10 starts the engine 1. That is, the engagement command is output to the lockup clutch 2a and the engine 1 start command is output. In this way, the rotation synchronization control is performed while the lockup clutch 2a is engaged. When the vehicle speed VSP is lower than the first predetermined vehicle speed V1, the lockup clutch 2a is engaged before the forward clutch 3a is rotationally synchronized in order to quickly execute the fuel cut, which will be described later in detail.

In step S103, the transmission controller 11 determines whether the forward clutch 3a is rotationally synchronized. Specifically, the transmission controller 11 determines whether the relationship between the engine rotation speed Ne and the primary rotation speed Npri satisfies the expression (1). The engine rotation speed Ne is detected by a signal from the engine rotation speed sensor 24. The primary rotation speed Npri is detected based on the signal from the primary rotation speed sensor 25.

|Ne-(R1×Npri)|≦N1 (1)

"R1" is a gear ratio of the forward/reverse switching mechanism 3 when the forward clutch 3a is engaged. “N1” is a preset first threshold value, and is a value that can be determined to be capable of suppressing the occurrence of engagement shock when engaging the forward clutch 3a with the lockup clutch 2a engaged. The first threshold N1 is smaller than the second threshold N2 described later.

In the present embodiment, since the turbine rotation speed of the torque converter 2 (the rotation speed Nin on the input side of the forward/reverse switching mechanism 3) is not detected, the forward clutch 3a is calculated using the engine rotation speed Ne and the primary rotation speed Npri. It is determined whether or not the rotation is synchronized.

The transmission controller 11 determines that the forward clutch 3a is rotationally synchronized when the expression (1) is satisfied, and determines that the forward clutch 3a is not rotationally synchronized when the expression (1) is not satisfied. When the vehicle speed VSP becomes low, the primary rotation speed Npri becomes low, the engine speed Ne becomes high when the engine 1 is started, and the process proceeds to step S104 when the forward clutch 3a is rotationally synchronized.

In step S104, the transmission controller 11 ends the rotation synchronization control and executes the engagement control. The transmission controller 11 increases the hydraulic pressure supplied to the forward clutch 3a and engages the forward clutch 3a.

In step S105, the engine controller 10 performs fuel cut to stop the fuel injection into the engine 1. As a result, the alternator 7 is driven by the rotation transmitted from the drive wheels, and alternator regeneration is performed. The power generated by the alternator regeneration is stored in the battery.

In step S106, the engine controller 10 starts the engine 1. When the vehicle speed VSP is equal to or higher than the first predetermined vehicle speed V1, the rotation synchronization control is executed with the lockup clutch 2a released.

In step S107, the transmission controller 11 determines whether the forward clutch 3a is rotationally synchronized. Specifically, the transmission controller 11 determines whether the relationship between the engine rotation speed Ne and the primary rotation speed Npri satisfies the expression (2).

|Ne-(R1×Npri)|≦N2 (2)

“N2” is a preset second threshold value, and is a value that can be determined to be able to suppress the occurrence of engagement shock when engaging the forward clutch 3a with the lockup clutch 2a released. The second threshold N2 is larger than the first threshold N1.

The transmission controller 11 determines that the forward clutch 3a is rotationally synchronized when the expression (2) is satisfied, and determines that the forward clutch 3a is not rotationally synchronized when the expression (2) is not satisfied. When the engine speed Ne is increased by the start of the engine 1 and the forward clutch 3a is rotationally synchronized, the process proceeds to step S108.

In step S108, the transmission controller 11 ends the rotation synchronization control and executes the engagement control. The transmission controller 11 increases the hydraulic pressure supplied to the forward clutch 3a and engages the forward clutch 3a.

Next, the case of canceling the sailing stop control will be described using a time chart. FIG. 3 is a time chart of a comparative example in which the vehicle speed VSP is lower than the first predetermined vehicle speed V1 and the sailing stop control is released in the state where the lockup clutch 2a is released.

In this comparative example, the input side rotation speed Nin of the forward/reverse switching mechanism 3 is detected, and the input side rotation speed Nin, the primary rotation speed Npri, and the forward/reverse switching mechanism 3 when the forward clutch 3a is engaged. The rotation synchronization of the forward clutch 3a is determined based on the gear ratio R1. Specifically, when Expression (3) is satisfied, it is determined that the forward clutch 3a is rotationally synchronized.

|Nin-(R1×Npri)|≦N3 (3)

"N3" is a preset threshold value and is set so that the occurrence of engagement shock is suppressed when the forward clutch 3a is engaged with the lockup clutch 2a released.

At time t0, the vehicle speed VSP becomes less than the first predetermined vehicle speed V1, the sailing stop control cancellation condition is satisfied, the sailing stop cancellation control is started, and the rotation synchronization control is started. As a result, the engine 1 is started, and the engine rotation speed Ne and the input-side rotation speed Nin increase. In FIG. 3, the engine rotation speed Ne is shown by a solid line, and a part of the input rotation speed Nin is shown by a broken line. Since the lockup clutch 2a is released, the input side rotation speed Nin is lower than the engine rotation speed Ne.

When the rotation synchronization control is started, the standby pressure is supplied to the forward clutch 3a as a preparatory step for quickly engaging the forward clutch 3a, and the clutch stroke of the forward clutch 3a increases.

At time t1, when the formula (3) is satisfied and it is determined that the forward clutch 3a is rotationally synchronized, the rotational synchronization control is ended and the engagement control is started. By executing the engagement control, the command pressure of the forward clutch 3a rapidly increases, the clutch stroke increases, and the forward clutch 3a is engaged.

At time t2, the fastening control ends, the sailing stop release control ends, and the normal traveling control starts. When the forward clutch 3a is engaged, engagement of the lockup clutch 2a is started. After time t2, the input rotation speed Nin and the primary rotation speed Npri match the rotation speed obtained by multiplying the gear ratio R1 of the forward/reverse switching mechanism 3 when the forward clutch 3a is engaged.

When the lockup clutch 2a is engaged after the forward clutch 3a is engaged when the vehicle speed VSP is less than the first predetermined vehicle speed V1 as in the comparative example, the torque converter 2 is operated until the lockup clutch 2a is engaged until the lockup clutch 2a is engaged. The driven machine such as the alternator 7 located on the upstream side cannot be driven by the rotation transmitted from the drive wheels.

In FIG. 3, the dotted line indicates the engine rotation speed Ne when the fuel cut is executed immediately after the forward clutch 3a is engaged in the state where the lockup clutch 2a is not engaged. When the fuel cut is executed while the lockup clutch 2a is not engaged, the alternator regeneration cannot be performed because the engine speed Ne is sharply reduced by the fuel cut.

In the comparative example, the alternator regeneration can be performed after the time t3 when the lockup clutch 2a is engaged, but the fuel cut is executed and the alternator regeneration cannot be performed between the times t2 and t3.

On the other hand, it is also conceivable to engage the lockup clutch 2a to perform rotation synchronization and to engage the forward clutch 3a. Next, this case will be described with reference to the time chart of FIG.

At time t0, the vehicle speed VSP becomes less than the first predetermined vehicle speed V1, the sailing stop control release condition is satisfied, the lockup clutch 2a is engaged, the sailing stop release control is started, and the rotation synchronization control is started. As a result, the engine rotation speed Ne and the input-side rotation speed Nin increase. When the lockup clutch 2a is engaged, the input side rotation speed Nin matches the engine rotation speed Ne.

Further, by supplying the standby pressure to the forward clutch 3a, the clutch stroke of the forward clutch 3a increases.

At time t1, when the formula (3) is satisfied and it is determined that the forward clutch 3a is rotationally synchronized, the rotational synchronization control is ended and the engagement control is started. As a result, the forward clutch 3a is engaged. When the lockup clutch 2a is engaged and the forward clutch 3a is engaged, when the rotation synchronization is determined under the same conditions as those in FIG. 3 in which the lockup clutch 2a is not engaged, there is no slip due to the torque converter 2 and the engine 1 acts as a load. Therefore, a pulling shock (fastening shock) occurs when the forward clutch 3a is fastened.

At time t2, the fastening control ends, the sailing stop release control ends, and the normal traveling control starts. Here, since the lock-up clutch 2a is engaged, the fuel cut can be performed immediately after the running control is started, and the alternator regeneration can be performed.

In this way, by engaging the lockup clutch 2a to perform rotation synchronization and engaging the forward clutch 3a, it is possible to quickly start alternator regeneration. However, if the rotation synchronization is determined under the same condition as when the lockup clutch 2a is released, a pull shock occurs when the forward clutch 3a is engaged.

Next, the case of using the present embodiment will be described with reference to the time chart of FIG. In FIG. 5, a part of the change in the rotation speed in FIG.

At time t0, the vehicle speed VSP becomes less than the first predetermined vehicle speed V1, the sailing stop control release condition is satisfied, the lockup clutch 2a is engaged, the sailing stop release control is started, and the rotation synchronization control is started. As a result, the engine rotation speed Ne and the input-side rotation speed Nin increase. When the lockup clutch 2a is engaged, the input side rotation speed Nin matches the engine rotation speed Ne.

Further, by supplying the standby pressure to the forward clutch 3a, the clutch stroke of the forward clutch 3a increases.

At time t1, if the formula (1) is satisfied and it is determined that the forward clutch 3a is rotationally synchronized, the rotational synchronization control is ended and the engagement control is started. As a result, the forward clutch 3a is engaged.

In the present embodiment, as the threshold value for determining the rotation synchronization with the lockup clutch 2a engaged, a first threshold value N1 different from the second threshold value N2 for determining the rotation synchronization with the lockup clutch 2a released. Set up. This makes it possible to suppress the occurrence of pulling shock even when the rotation synchronization is determined with the lockup clutch 2a being engaged and the forward clutch 3a is engaged.

The effects of the embodiment of the present invention will be described.

When canceling the sailing stop control, if the vehicle speed VSP becomes less than the first predetermined vehicle speed V1, the forward clutch 3a is engaged while the lockup clutch 2a is engaged. As a result, after releasing the sailing stop control, the rotation of the drive wheels can be transmitted to the driven machine such as the alternator 7 and the mechanical oil pump 6m at an early stage, and the alternator regeneration and the hydraulic pressure supply by the mechanical oil pump 6m can be promptly performed. It can be started and the electricity cost can be improved. Further, the fuel cut of the engine 1 which is carried out due to the decrease in the vehicle speed VSP can be promptly started, and the fuel consumption can be improved (effects corresponding to claims 1, 2 and 7 ).

When canceling the sailing stop control, when the vehicle speed VSP is equal to or higher than the first predetermined vehicle speed V1, and the predetermined neutral traveling control cancellation condition is satisfied except when the vehicle speed VSP is lower than the first predetermined vehicle speed V1. The forward clutch 3a is engaged with the lockup clutch 2a released. As a result, the torque converter 2 is in the converter state when the forward clutch 3a is engaged, and the occurrence of engagement shock can be suppressed (effects corresponding to claims 1 and 7).

By executing the rotation synchronization control when canceling the sailing stop control, it is possible to suppress the engagement shock when the forward clutch 3a is engaged. In the present embodiment, a sensor for detecting the rotation speed Nin on the input side of the forward/reverse switching mechanism 3 is not provided, and rotation synchronization is determined using the engine rotation speed Ne and the primary rotation speed Npri.

In such a case, even if the rotation speed difference between the engine rotation speed Ne and the primary rotation speed Npri is the same, the rotation speed difference before and after the forward clutch 3a, that is, depending on whether the lockup clutch 2a is engaged or released. The rotation synchronization state is different.

In the present embodiment, the rotation synchronization is accurately determined regardless of the state of the lockup clutch 2a by changing the threshold value for determining the rotation synchronization depending on whether the lockup clutch 2a is engaged or released. However, it is possible to suppress the occurrence of engagement shock when the forward clutch 3a is engaged (effect corresponding to claim 4 ).

Specifically, the first threshold value N1 for determining rotation synchronization with the lockup clutch 2a engaged is set to be smaller than the second threshold value N2 for determining rotation synchronization with the lockup clutch 2a released. Thereby, regardless of the state of the lockup clutch 2a, it is possible to suppress the occurrence of engagement shock when engaging the forward clutch 3a (effect corresponding to claim 5 ).

Even when the vehicle speed VSP becomes less than the first predetermined vehicle speed V1 and the sailing stop control is canceled, the engine 1 needs to be started in order to perform the rotation synchronization control. Therefore, when canceling the sailing stop control, the engine 1 is started. To start. After the forward clutch 3a is engaged, fuel injection to the engine 1 is stopped and fuel cut is performed. As a result, it is possible to suppress the occurrence of a shock when engaging the forward clutch 3a and improve the fuel consumption (the effect corresponding to claim 6 ).

Although the embodiment of the present invention has been described above, the above embodiment merely shows a part of the application example of the present invention, and the technical scope of the present invention is limited to the specific configuration of the above embodiment. Absent.

In addition to the configuration of the above embodiment, for example, an accumulator may be provided in an oil passage that supplies hydraulic pressure to the forward clutch 3a. Further, a dish plate may be provided between the piston and the plate that fastens the forward clutch 3a according to the hydraulic pressure.

In the above embodiment, the automatic transmission 15 having the forward/reverse switching mechanism 3 has been described, but the automatic transmission 15 may have an auxiliary transmission mechanism. The forward/reverse switching mechanism 3 and the auxiliary transmission mechanism function as a power transmission mechanism. Further, the automatic transmission 15 may be configured to have a stepped transmission or a toroidal type continuously variable transmission instead of the continuously variable transmission 4.

In the above-described embodiment, the formulas (1) and (2) are used as a method for determining whether the forward clutch 3a is rotationally synchronized, but, for example, the formulas (4) and (5) are used to determine Good.

|R1-Ne/Npri|≦N4 (4)
|R1-Ne/Npri|≦N5 (5)

“N4” is a preset fourth threshold value and is a value that can be determined to be capable of suppressing the occurrence of engagement shock when engaging the forward clutch 3a with the lockup clutch 2a engaged. “N5” is a preset fifth threshold value, which is a value that can be determined to suppress the occurrence of engagement shock when engaging the forward clutch 3a with the lockup clutch 2a released, and N4. Greater than.

The method for determining whether or not the forward clutch 3a is rotationally synchronized is not limited to Expression (1), Expression (2), Expression (4), and Expression (5). It is only necessary to accurately determine the synchronization and suppress the occurrence of the fastening shock.

In the above embodiment, the sailing stop control is described as an example of the neutral traveling control. However, the neutral traveling control may be, for example, sailing control in addition to the sailing stop control. That is, while the engine stop condition is satisfied, the engine 1 that is the drive source is stopped during traveling, and during the neutral traveling in which the automatic transmission 15 is in the neutral state, the neutral release condition is satisfied and the engine 1 is activated. The above control can be applied when starting and engaging the forward clutch 3a.

The sailing control is executed by the transmission controller 11 and the engine controller 10 when the sailing satisfaction condition is satisfied. The sailing establishment conditions are, for example, the following (a) to (d). (A) The shift lever 40 is in the D range. (B) The vehicle speed VSP is equal to or higher than the second predetermined vehicle speed (predetermined vehicle speed) V2. (C) The accelerator pedal 41 is not depressed. (D) The brake pedal 42 is not depressed. The second predetermined vehicle speed V2 is a low vehicle speed lower than the first predetermined vehicle speed V1.

The sailing satisfaction condition is satisfied when all the conditions (a) to (d) are satisfied, and is not satisfied when any of the conditions (a) to (d) is not satisfied. The sailing cancellation condition is that any of (a) to (d) is not satisfied during the sailing control, but the sailing satisfaction condition and the sailing cancellation condition may be different conditions.

In the above embodiment, the lockup clutch 2a is released during the sailing stop control, but if the sailing stop condition is satisfied while the lockup clutch 2a is engaged, the lockup clutch 2a is engaged during the sailing stop control. You may maintain it in the state which was carried out. As a result, it is not necessary to engage the lockup clutch 2a when releasing the sailing stop control, the number of times the lockup clutch 2a is engaged can be reduced, and the durability of the lockup clutch 2a can be improved. Effect corresponding to 3).

When performing such neutral traveling control (sailing stop control), the lockup clutch 2a is released when a predetermined neutral traveling control cancellation condition is satisfied, and the forward clutch is released with the lockup clutch 2a released. Fasten 3a.

The "predetermined neutral traveling control cancellation condition" is not limited, but may include at least one or more of the following conditions, for example. As a result, the forward clutch 3a is engaged with the lockup clutch 2a released, so that the engagement shock of the forward clutch 3a can be reduced.

(A) The accelerator pedal 41 is depressed and the accelerator pedal opening APO becomes smaller than the predetermined opening APO1 (0<APO<APO1).
(B) The accelerator pedal 41 is depressed, and the accelerator pedal opening APO becomes equal to or larger than the predetermined opening APO1 (APO1≦APO).
(C) The brake pedal 42 is depressed.
(D) It is possible to add a condition other than (a) to (c) as the neutral traveling control cancellation condition, and in that case, the added condition is, for example, when the road becomes a predetermined slope or more (boarding For example, when the vehicle approaches a road) or when the vehicle is changed to a low speed range (L range, S range) or the like.

In addition, it is preferable to include at least the condition (a) as the predetermined neutral traveling control cancellation condition from the viewpoint of preventing a fastening shock.

In the above embodiment, the case where the engine 1 is the drive source has been described. However, the drive source may be, for example, a motor or the engine 1 and the motor.

In the above embodiment, the transmission controller 11 and the engine controller 10 may constitute a single controller. Further, at least one of the transmission controller 11 and the engine controller 10 may be composed of a plurality of controllers.

1: Engine (drive source)
2: Torque converter 2a: Lockup clutch 3: Forward/reverse switching mechanism 3a: Forward clutch (fastening element)
5: Hydraulic control circuit 6m: Mechanical oil pump (driven machine)
7: Alternator (driven machine)
10: Engine controller (control unit)
11: Transmission controller (control unit)
15: Automatic transmission 21: Accelerator pedal opening sensor 24: Engine speed sensor 25: Primary speed sensor 26: Vehicle speed sensor

Claims (7)

Drive source,
A driven machine driven by the drive source,
In the power transmission path, a torque converter provided downstream of the drive source and the driven machine and having a lock-up clutch, and a fastening element provided in the power transmission path downstream of the torque converter. And an automatic transmission having:
When the vehicle speed becomes lower than a predetermined vehicle speed during the neutral travel control in which the automatic transmission is in the power cut-off state while the vehicle is traveling, a control unit that engages the engagement element with the lockup clutch engaged is provided. ,
State wherein, in the state of the vehicle speed is above the predetermined vehicle speed, the predetermined neutral travel control release conditions other than when the vehicle speed becomes less than the predetermined vehicle speed is when a condition is satisfied, that releases the lockup clutch Fasten the fastening element with,
A vehicle control device characterized by the above. The control device for a vehicle according to claim 1,
The driven machine is an alternator or a mechanical oil pump,
A vehicle control device characterized by the above. The control device for a vehicle according to claim 1 or 2, wherein
When the control unit is in a state in which the lockup clutch is engaged before the neutral traveling control, maintains the state in which the lockup clutch is engaged during the neutral traveling control,
A vehicle control device characterized by the above. The vehicle control device according to any one of claims 1 to 3,
When the control unit performs the rotation synchronization of the fastening element and fastens the fastening element in a state in which the lockup clutch is released, when fastening the fastening element from the state in which the neutral traveling control is being performed. Of the rotation synchronization and the rotation synchronization when the fastening element is fastened in a state where the lockup clutch is fastened are determined by different thresholds,
A vehicle control device characterized by the above. The vehicle control device according to claim 4,
The first threshold for determining the rotation synchronization when engaging the engagement element with the lockup clutch engaged determines the rotation synchronization when engaging the engagement element with the lockup clutch released. Smaller than the second threshold
A vehicle control device characterized by the above. The control device for a vehicle according to any one of claims 1 to 5, wherein
The control unit stops the drive source during the neutral travel control, and when fastening the fastening element from a state in which the neutral travel control is being executed, the fastening element is started after starting the drive source. Rotation synchronization of, and stop the drive source after fastening the fastening element,
A vehicle control device characterized by the above. Drive source,
A driven machine driven by the drive source,
In a power transmission path, a torque converter provided downstream of the drive source and the driven machine and having a lockup clutch, and a fastening element provided in the power transmission path downstream of the torque converter. And an automatic transmission having:
During neutral travel control to put the automatic transmission in a power cut-off state while the vehicle is traveling, when the vehicle speed becomes less than a predetermined vehicle speed, the fastening element is fastened with the lockup clutch fastened,
In the state of the vehicle speed is above the predetermined vehicle speed, when the predetermined neutral travel control release conditions other than when the vehicle speed becomes less than the predetermined vehicle speed is satisfied, the fastening element in a state of releasing the lock-up clutch Conclude,
A vehicle control method characterized by the above.

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