JP2021095029A - Hybrid vehicle control device - Google Patents

Abstract

To provide a hybrid vehicle control device capable of preventing fail-safe control to disengage a clutch mechanism from being unable to be executed in a travel mode with a clutch mechanism engaged.SOLUTION: A hybrid vehicle control device: determines whether or not engaging operation to engage a clutch mechanism arranged between an internal combustion engine and drive wheels and disengaging operation to disengage the clutch mechanism are available (Step S3); and, when determining that the engaging operation and the disengaging operation of the clutch mechanism are available, allows a travel mode to be switched from a first travel mode enabling a vehicle to travel by torque of an electric motor connected to the drive wheel or another drive wheel with the clutch mechanism disengaged to a second travel mode enabling the vehicle to travel by torque transmitted from the internal combustion engine to the drive wheel with the clutch mechanism engaged (Step S5).SELECTED DRAWING: Figure 2

Description

The present invention has a mode in which the power of an internal combustion engine is converted into electric power and the electric power is supplied to the electric motor to transmit the output torque of the electric motor to the drive wheels for traveling, and the output torque of the internal combustion engine is transmitted to the drive wheels. It relates to a control device of a hybrid vehicle which can set a mode of traveling.

Patent Document 1 describes a rear wheel drive device including an engine, a rear motor having a power generation function connected to the engine, a clutch mechanism capable of interrupting torque transmission between the engine and the rear motor and the rear wheels, and the rear motor. Described is a hybrid vehicle equipped with a front-wheel drive device configured to output drive torque from a front motor to drive the front wheels by supplying power generated by the engine or power charged to the battery. There is. This hybrid vehicle engages the clutch mechanism with the series driving mode in which the clutch mechanism is released, the power of the engine is converted into electric power by the rear motor, and the electric power is supplied to the front motor to run, and at least the engine torque is rearranged. It is possible to set an engine driving mode (or a parallel driving mode) in which the vehicle travels by transmitting power to the wheels.

Patent Document 2 describes an engine, a generator connected to the engine, a clutch mechanism capable of interrupting torque transmission between the engine and the drive wheels, and a motor connected to the drive wheels so as to be able to transmit torque without using the clutch mechanism. A control device for a hybrid vehicle equipped with and is described. Similar to Patent Document 1, this hybrid vehicle is configured to release the clutch mechanism to set the series traveling mode, and engage the clutch mechanism to set the engine traveling mode (or parallel traveling mode). Then, when the clutch mechanism is engaged to switch from the series driving mode to the parallel driving mode, if the clutch mechanism does not engage even after a lapse of a predetermined time from the start of engaging the clutch mechanism, the vehicle stops. During that time, it is configured to prohibit switching to the parallel driving mode.

JP-A-2019-123387 Japanese Unexamined Patent Publication No. 2013-123964

In the hybrid vehicle described in Patent Document 1 and Patent Document 2, the transmission of torque between the engine and the drive wheels can be cut off by releasing the clutch mechanism. Therefore, when some kind of fail occurs in the vehicle and there is a request to cut off the transmission of torque between the engine and the drive wheels, it is preferable to perform fail-safe control for releasing the clutch mechanism. However, despite the failure that the clutch mechanism cannot be released, when the drive mode is switched to the driving mode set by engaging the clutch mechanism, the torque transmission between the engine and the drive wheels as described above is cut off. When there is a request, it may not be possible to properly perform fail-safe control.

The present invention has been made by paying attention to the above technical problems, and is a control device for a hybrid vehicle capable of suppressing the failure to execute fail-safe control for releasing the clutch mechanism in a traveling mode in which the clutch mechanism is engaged. It is intended to be provided.

In order to achieve the above object, the present invention comprises an internal combustion engine, a generator connected so as to be able to transmit torque to a rotating member provided in a path for transmitting torque from the internal combustion engine to a drive wheel, and the rotating member. A clutch mechanism that cuts off the transmission of torque between the internal combustion engine and the drive wheels on the drive wheel side, and an electric motor that is connected to the drive wheels or other drive wheels different from the drive wheels so that torque can be transmitted. The clutch mechanism is engaged with the first traveling mode in which the clutch mechanism is released, the power of the internal combustion engine is converted into electric power by the generator, and the power is output from the electric motor to travel. Then, in a control device of a hybrid vehicle provided with a drive system capable of setting a second travel mode in which the drive torque of the internal combustion engine is transmitted to the drive wheels to travel, a controller for controlling the drive system is provided. The controller determines whether or not an engagement operation for engaging the clutch mechanism and a release operation for releasing the clutch mechanism are possible, and the engagement operation and the release operation of the clutch mechanism are performed. It is characterized in that it is configured to allow switching from the first traveling mode to the second traveling mode when it is determined that it is possible.

According to the present invention, it is determined whether or not the clutch mechanism that cuts off the transmission of torque between the internal combustion engine and the drive wheels can perform the engagement operation and the disengagement operation, and the engagement operation and the disengagement operation are performed. When it is possible to perform the above, it is permitted to switch from the first traveling mode set by releasing the clutch mechanism to the second traveling mode set by engaging the clutch mechanism. That is, the condition for switching from the first traveling mode to the second traveling mode includes that the clutch mechanism operates normally. Therefore, even if some failure occurs in the hybrid vehicle after switching to the second driving mode, the clutch mechanism can operate normally, so that the torque transmission between the internal combustion engine and the drive wheels should be appropriately cut off. Can be done. That is, it is possible to reduce the possibility that the fail-safe control cannot be executed.

It is a schematic diagram for demonstrating an example of the hybrid vehicle in embodiment of this invention. It is a flowchart for demonstrating the control example which executes the operation check of the switching clutch when the series running mode is set. It is a flowchart for demonstrating the control example which determines whether or not the switching clutch mechanism operates normally based on the hydraulic pressure. It is a flowchart for demonstrating the control example which determines whether or not the switching clutch mechanism operates normally based on an input rotation speed. It is a flowchart for demonstrating the control example of the switching determination of a traveling mode. It is a time chart for demonstrating the change of the traveling mode switching, the operation confirmation state of the switching clutch 7, and the state of the flag which shows that the switching clutch is normal when the control example shown in FIG. 2 is executed. It is a flowchart for demonstrating the control example which executes the operation check of the switching clutch in the transitional period of switching from a parallel running mode to a series running mode.

FIG. 1 shows a schematic diagram for explaining an example of a hybrid vehicle according to an embodiment of the present invention. The hybrid vehicle (hereinafter, simply referred to as a vehicle) 1 shown in FIG. 1 is a four-wheel drive vehicle based on a front engine / rear wheel drive vehicle (FR vehicle), and has engines (Eng) 2 and 2 as driving force sources. It includes two motors (Rr-MG, Fr-MG) 3 and 4. The engine 2 and the rear motor 3 drive the pair of rear wheels 5, and the front motor 4 drives the pair of front wheels 6.

Specifically, the engine 2 is arranged in a so-called vertical position toward the rear of the vehicle 1. The engine 2 is, for example, an internal combustion engine such as a gasoline engine or a diesel engine. In the case of a gasoline engine, the opening degree (intake air amount) of the throttle valve, the fuel injection amount, the ignition timing, and the like are electrically controlled. To. In the case of a diesel engine, the injection amount of fuel, the injection timing of fuel, the opening degree of a valve in an EGR (Exhaust Gas Recirculation) system, and the like are electrically controlled.

The rear motor 3, the switching clutch 7, which is a hydraulic clutch mechanism, and the rear transmission mechanism 8 are arranged in this order on the output side of the engine 2 and on the same axis as the engine 2, and the output shaft 9 of the engine 2 And the rotor shaft of the rear motor 3 is connected to the input shaft 10 of the rear transmission mechanism 8 via the switching clutch 7. The rear motor 3 is supplied with a function as a generator (power generation function) that converts at least a part of the power of the engine 2 into electric power by outputting braking torque so as to reduce the rotation speed of the engine 2. It has a function (electric function) as an electric motor that is driven by the engine and outputs a driving torque so as to increase the rotation speed of the engine 2. That is, the rear motor 3 is a motor / generator having a power generation function, and is composed of, for example, an AC motor such as a permanent magnet type synchronous motor or an induction motor. A battery (not shown) is connected to the rear motor 3 via an inverter, and the electric power generated by the rear motor 3 can be charged to the battery, and the electric power of the battery can be supplied to the rear motor 3.

Further, a mechanical oil pump 11 driven by rotation of the engine 2 and the rear motor 3 is provided on the output shaft 9 of the engine 2 or the output shaft of the rear motor 3. In the example shown in FIG. 1, an oil pump 11 is provided on the output shaft 9 of the engine 2.

A regulator valve 12 that adjusts the oil pressure discharged from the oil pump 11 to a predetermined oil pressure is connected to the oil pump 11, and when a hydraulic pressure equal to or higher than the oil pressure set by the regulator valve 12 is generated, the regulator Excess oil is drained from the valve 12 to an oil pan (not shown). Further, a control valve 13 for controlling the flood pressure supplied to the switching clutch 7 is connected to the regulator valve 12. Therefore, the control valve 13 controls the oil pressure supplied to the switching clutch 7 with reference to the original pressure adjusted by the regulator valve 12.

In the example shown here, the switching clutch 7 is configured to selectively transmit and disengage torque between the engine 2 and the rear motor 3 and the pair of rear wheels 5. The switching clutch 7 shown in FIG. 1 has a friction plate 7a connected to the rotor shaft of the rear motor 3 and a friction plate 7b connected to the input shaft 10 of the rear transmission mechanism 8. Then, as the oil pressure supplied from the control valve 13 increases, the friction plates 7a and 7b come into contact with each other so that the torque corresponding to the contact pressure can be transmitted from the engine 2 and the rear motor 3 to the pair of rear wheels 5. Be connected. Further, as the flood pressure decreases, the friction plates 7a and 7b are separated from each other, and the engine 2 and the first motor 3 are separated from the pair of rear wheels 5. The switching clutch 7 may be composed of a multi-plate clutch having a plurality of friction plates 7a and a plurality of friction plates 7b, and the plurality of friction plates 7a and the plurality of friction plates 7b are alternately arranged.

The rear transmission mechanism 8 is a mechanism that can appropriately change the ratio (gear ratio) between the input rotation speed and the output rotation speed, and is a stepped transmission that can change the gear ratio step by step, and a gear ratio. It can be configured by a continuously variable transmission or the like that can be changed continuously. Further, the rear transmission mechanism 8 is preferably configured so that torque can be transmitted by engaging with the rear transmission mechanism 8 and the torque transmission can be cut off by releasing the rear transmission mechanism 8 to set the neutral state, and the oil described above can be set. Even when the pump 11 is stopped, it is preferable that the gear ratio can be changed by an electromagnetic actuator or the like, and the pump 11 can be switched to the neutral state. Hereinafter, the rear transmission mechanism 8 capable of setting the neutral state will be described as an example.

The rear propeller shaft 14 is connected to the rear transmission mechanism 8. The rear propeller shaft 14 extends rearward from the rear transmission mechanism 8 in the front-rear direction of the vehicle 1, and the rear differential gear unit 15 is connected to the rear propeller shaft 14. The left and right rear wheels 5 are connected to the rear differential gear unit 15 via a pair of rear drive shafts 16.

The front motor 4 described above is connected to the left and right front wheels 6 so as to be able to transmit power. In the example shown here, the front motor 4 has a function as a motor that outputs a drive torque that increases the number of rotations of the pair of front wheels 6 by supplying electric power from a battery (not shown), and the pair of front wheels 6. By outputting braking torque that lowers the number of revolutions, it has a function as a generator that converts the kinetic energy of the vehicle 1 (or front wheel 6) into electric power to charge the battery. That is, the front motor 4 is a motor generator having a power generation function like the rear motor 3, and is composed of, for example, an AC motor such as a permanent magnet type synchronous motor or an induction motor. Further, the rear motor 3 and the front motor 4 described above are connected to each other so that electric power can be exchanged via an inverter. For example, the electric power generated by the rear motor 3 is directly supplied to the front motor 4 to supply the front motor. It is also possible to output the drive torque from 4.

The front transmission mechanism 17, the front propeller shaft 18, and the front differential gear unit 19 are arranged in this order on the same axis as the front motor 4 and in the front-rear direction of the vehicle 1 in front of the front motor 4, and the front differential gears thereof. A pair of front wheels 6 are connected so as to be able to transmit torque via a front drive shaft 20 connected to the unit 19. The front transmission mechanism 17 can be configured by, for example, a stepped transmission mechanism capable of setting a direct connection stage and a reduction stage.

The vehicle 1 having the configuration shown in FIG. 1 can be set to an engine traveling mode in which the vehicle 1 travels mainly with the engine torque and an EV traveling mode in which the vehicle 1 travels mainly with the driving torque of the front motor 4. This engine running mode is a running mode set by engaging the switching clutch 7, and in addition to the mode in which torque is output from only the engine 2 to run, the engine torque and the driving torque of the front motor 4 are combined. It includes a so-called parallel traveling mode in which the vehicle 1 is driven by the vehicle 1. In this parallel traveling mode, in addition to the engine torque and the driving torque of the front motor 4, the driving torque can be output from the rear motor 3 for traveling.

Further, the EV driving mode is a driving mode set by releasing the switching clutch 7, and supplies electric power charged to a battery (not shown) to the front motor 4 for driving and powers the engine 2. The rear motor 3 converts the electric power into electric power, and the electric power is energized to the front motor 4 to run, including a so-called series running mode. In the series traveling mode, in addition to the electric power supplied from the rear motor 3 to the front motor 4, the battery can supply electric power to the front motor 4 for traveling.

An electronic control device (hereinafter referred to as an ECU) 21 for controlling the engine 2, the rear motor 3, the front motor 4, the transmission mechanisms 8 and 17, the regulator valve 12, the control valve 13, and the like described above is provided. The ECU 21 is mainly composed of a microcomputer, like a conventionally known electronic control device, and signals are input from various sensors provided in the vehicle 1, and the input signals and the input signals are combined with the ECU 21. A command signal is output to the engine 2, the rear motor 3, the front motor 4, the transmission mechanisms 8 and 17, the regulator valve 12, the control valve 13, and the like based on the calculation formulas and maps stored in advance.

The map stored in the ECU 21 is, for example, a map for setting a driving mode based on a required driving force and a vehicle speed based on an accelerator operation amount of a driver, a remaining charge of a battery, and the like, and each transmission mechanism 8 , 17 is a map for determining the gear ratio to be set.

When the vehicle 1 configured as described above is running with the engine running mode set, if any failure occurs, torque is transmitted between the engine 2 and the rear wheels 5 in order to make the vehicle 1 emergency stop. It may be required to shut off, that is, to release the switching clutch 7. Therefore, it is preferable to set the engine running mode when the switching clutch 7 operates normally. However, since the switching clutch 7 is controlled based on the oil pressure generated by the oil pump 11, it is possible to determine whether or not the switching clutch 7 operates normally when the engine 2 is stopped. Can not. That is, it is not possible to determine whether or not the switching clutch 7 operates normally at the time when the vehicle 1 is started (IG on) or when the vehicle 1 is switched to the ready-on state in which the vehicle can run. Further, when the engine is running with the engine running mode set, more specifically, when the driving torque of the engine 2 is transmitted to the rear wheels 5 and the car is running, the operation of releasing the switching clutch 7 is confirmed. If this is done, the driving force will be reduced, which may cause the driver to feel uncomfortable.

Therefore, the control device according to the embodiment of the present invention is configured to set the engine running mode when it is confirmed that the switching clutch 7 can operate normally, and further transmits the engine torque to the rear wheels 5. It is configured to check the operation of the switching clutch 7 when there is no request or when the transmitted torque is small. An example of the control is shown in FIG. The control example shown in FIG. 2 is configured to execute the operation check of the switching clutch 7 in the series running mode. Explaining the control example, first, it is determined whether or not the series running mode is set (step S1). This step S1 can be determined by confirming the traveling mode determined based on the map stored in the ECU 21 described above, or whether the switching clutch 7 is released and the rear motor 3 is generating power. It can be determined based on whether or not, or whether or not the drive torque is output from the front motor 4.

If it is negatively determined in step S1 because the set driving mode is not the series driving mode, this routine is temporarily terminated as it is. On the contrary, when a positive judgment is made in step S1 due to the setting of the series running mode, it is judged whether or not the condition for executing the operation check of the switching clutch 7 is satisfied (step S2). ). This step S2 can be determined based on whether or not the engine 2 has been warmed up, that is, whether or not the engine 2 can operate stably. Specifically, it can be determined based on whether or not the temperature of the cooling water of the engine 2 is equal to or higher than a predetermined temperature.

If it is negatively determined in step S2 because the condition for executing the operation check of the switching clutch 7 is not satisfied, such as when the engine 2 is at a low temperature, this routine is temporarily terminated as it is. On the contrary, when the condition for executing the operation check of the switching clutch 7 is satisfied and it is positively determined in step S2, the operation check of the switching clutch 7 is executed (step S3). Specifically, the subroutine shown in FIG. 3 or FIG. 4 is executed.

In the operation check shown in FIG. 3, the switching clutch 7 operates normally based on the detection value of the oil pressure sensor provided on the output side of the regulator valve 12 and the detection value of the oil pressure sensor provided on the output side of the control valve 13. Determine if it can be done. Specifically, first, the rear transmission mechanism 8 is switched to the neutral state (step S301). In the operation check of the switching clutch 7, the engine 2 is rotated to generate an electric pressure, and the switching clutch 7 is engaged and released. Therefore, when the switching clutch 7 is engaged, the engine torque is increased. This is to suppress the change in driving force transmitted to the rear wheels 5.

Then, with the engine 2 being driven, the original pressure is set to be less than the first predetermined pressure (step S302), and it is determined whether or not the original pressure has risen to the first predetermined pressure or more (step S303). In this step S303, it is determined whether or not the regulator valve 12 is able to drain the oil normally. Therefore, for example, when the drain port is clogged or the solenoid for adjusting the original pressure is failing, and the original pressure rises to the first predetermined pressure or more, in step S303. If it is determined affirmatively, it is determined that an abnormality has occurred in which the switching clutch 7 cannot operate normally (step S304).

On the contrary, when it is negatively determined in step S303 that the original pressure is less than the first predetermined pressure, the control valve is in a state where the engine rotation speed is stably rotating at the predetermined rotation speed or higher. While closing the valve 13, the regulator valve 12 is controlled so that the original pressure becomes the second predetermined pressure (step S305), and the original pressure does not rise to the second predetermined pressure, or the output side of the control valve 13 It is determined whether or not the oil pressure (hereinafter referred to as control pressure) has increased (step S306). This step S306 is a step for determining whether or not the drain port of the regulator valve 12 can be closed and whether or not the control valve 13 can be closed. In other words, it is determined at the same time whether or not the original pressure can be increased to the extent that the switching clutch 7 is engaged, and whether or not the switching clutch 7 can be released by closing the input port of the control valve 13. It is a step for.

Therefore, if the original pressure does not rise to the second predetermined pressure, the switching clutch 7 may not be engaged, and if the control pressure rises, the switching clutch 7 cannot be released. there is a possibility. Therefore, if a positive determination is made in step S306, it is determined that an abnormality has occurred in which the switching clutch 7 cannot operate normally (step S304).

On the contrary, when the original pressure rises to the second predetermined pressure and the control pressure does not rise, which is negatively determined in step S306, the third predetermined pressure is such that the switching clutch 7 engages. The control valve 13 is controlled so that the control pressure rises to (step S307), and it is determined whether or not the control pressure has risen to the third predetermined pressure (step S308). This step S308 is a step for determining whether or not the output port of the control valve 13 can be opened to engage the switching clutch 7, and therefore the control pressure does not rise to the third predetermined pressure. As a result, if a negative determination is made in step S308, it may not be possible to engage the switching clutch 7, so it is determined that an abnormality has occurred in which the switching clutch 7 cannot operate normally (step S304). ).

On the contrary, when the control pressure rises to the third predetermined pressure and is positively determined in step S308, the regulator valve 12 is controlled so that the original pressure becomes equal to or less than the fourth predetermined pressure (step). S309), it is determined whether or not the original pressure and the control pressure have decreased (step S310). That is, it is determined whether or not the engaged switching clutch 7 can be released. If it is negatively determined in step S310 because the original pressure and the control pressure do not decrease, the switching clutch 7 may not be released normally when the switching clutch 7 is engaged, so that the switching clutch 7 is normal. It is determined that an abnormality that cannot be operated has occurred (step S304).

On the contrary, when the positive determination is made in step S310 due to the decrease in the original pressure and the control pressure, the switching clutch 7 can operate normally, so that it is determined to be normal (step S311). Terminate the routine once. When step S304 is executed, the flag indicating that the switching clutch 7 is abnormal is switched on, and when step S311 is executed, the flag indicating that the switching clutch 7 is normal is turned on. You may switch.

In the control example shown in FIG. 3, it is determined whether or not the switching clutch 7 is normal by detecting the original pressure and the control pressure. However, by engaging the switching clutch 7, the input rotation speed of the switching clutch 7 (that is, the engine rotation speed) and the output rotation speed of the switching clutch 7 (that is, the input rotation speed of the rear transmission mechanism 8) match. Since releasing the switching clutch 7 causes a difference in their rotation speeds, it may be determined whether or not the switching clutch 7 is normal based on the detected value of the rotation speeds.

A flowchart for explaining the control example is shown in FIG. In the control example shown in FIG. 4, similarly to step S301 and step S302 described above, the rear transmission mechanism 8 is switched to the neutral state (step S321), the original pressure is set to less than the first predetermined pressure, and the engine 2 is driven. (Step S322). Then, it is determined whether or not the input rotation speed of the rear transmission mechanism 8 is equal to or higher than the first predetermined rotation speed (step S323). By executing step S321 described above, the torque transmission path between the input shaft 10 of the rear transmission mechanism 8 and the drive wheels (rear wheels 5) is cut off, and here, positive in step S1. Since it is determined to be in the series running mode, the switching clutch 7 is released. Therefore, if there is no abnormality in the regulator valve 12 and the control valve 13, the input shaft 10 of the rear transmission mechanism 8 is stopped without applying torque. Therefore, in step S323, it is determined by the input rotation speed whether or not the oil pressure is unintentionally supplied to the switching clutch 7 via the regulator valve 12 and the control valve 13. Therefore, if it is positively determined in step S323 that the input rotation speed is equal to or higher than the first predetermined rotation speed, it is determined that an abnormality has occurred in which the switching clutch 7 cannot operate normally (step S324).

On the contrary, when the input rotation speed is less than the first predetermined rotation speed and is negatively determined in step S323, the engine rotation speed becomes stable at the predetermined rotation speed or more as in step S305 described above. The control valve 13 is closed and the regulator valve 12 is controlled so that the original pressure becomes the second predetermined pressure (step S325), and the input rotation speed is equal to or higher than the second predetermined rotation speed. (Step S326). This step S326 is the same as the above-mentioned step S323, and since the control valve 13 is closed, the switching clutch 7 is normally released, so that the input shaft 10 is stopped. Become. On the other hand, when the input shaft 10 is rotating, some failure occurs in the control valve 13 and the switching clutch 7 is engaged (including slip). Therefore, here, it is determined whether or not the control valve 13 is normal based on the input rotation speed. Therefore, the second predetermined rotation speed in step S326 and the first predetermined rotation speed in step S323 may be the same rotation speed.

If it is positively determined in step S326 because the input rotation speed is equal to or higher than the second predetermined rotation speed, it is determined that an abnormality has occurred in which the switching clutch 7 cannot operate normally (step S324). On the contrary, when the input rotation speed is less than the second predetermined rotation speed and it is negatively determined in step S326, the switching clutch 7 is engaged in the same manner as in step S307 described above. 3 The control valve 13 is controlled so that the control pressure rises to a predetermined pressure (step S327). When the control valve 13 operates normally, the control pressure rises and the switching clutch 7 switches to the engaged state, and as a result, the engine speed and the input speed become the same speed. On the other hand, when the control valve 13 does not operate normally, the control pressure does not increase, the switching clutch 7 is released, and the input rotation speed does not increase.

Therefore, following step S327, it is determined whether or not the input rotation speed is equal to or higher than the third predetermined rotation speed (step S328). The third predetermined rotation speed can be set to the same rotation speed as the engine rotation speed. If the input rotation speed is less than the third predetermined rotation speed and is negatively determined in step S328, the switching clutch 7 may not be engaged, so that the switching clutch 7 is normal. It is determined that an abnormality that cannot be operated has occurred (step S324).

On the contrary, when it is positively determined in step S328 that the input rotation speed is equal to or higher than the third predetermined rotation speed, the original pressure is set to be equal to or less than the fourth predetermined pressure as in step S309 described above. Control the regulator valve 12 (step S329). When the regulator valve 12 is controlled so that the original pressure becomes equal to or lower than the fourth predetermined pressure in a state where the input rotation speed is increased to the third predetermined rotation speed by the above step S328, the regulator valve 12 and the control valve 13 are controlled. If it operates normally, the switching clutch 7 is released, and the input rotation speed gradually decreases according to the sliding resistance of the rear transmission mechanism 8. Therefore, following step S329, it is determined whether or not the input rotation speed has decreased to the fourth predetermined rotation speed or less (step S330). The fourth predetermined rotation speed in step S330 is determined, for example, when a predetermined time has elapsed from the execution of step S329, and the rotation speed that decreases during the predetermined time period is determined in advance from the sliding resistance or the like. The rotation speed is set by subtracting the decreasing rotation speed from the third predetermined rotation speed described above.

If it is negatively determined in step S330 because the input rotation speed has not decreased to the fourth predetermined rotation speed or less, it may not be possible to release the clutch 7 normally when the switching clutch 7 is engaged. Therefore, it is determined that an abnormality has occurred in which the switching clutch 7 cannot operate normally (step S324).

On the contrary, when the input rotation speed is lowered to the fourth predetermined rotation speed or less and is positively determined in step S330, the switching clutch 7 can operate normally, so that it is determined to be normal. (Step S331), this routine is temporarily terminated. When step S324 is executed, the flag Fok indicating that the switching clutch 7 is abnormal is switched on, and when step S331 is executed, the flag Fok indicating that the switching clutch 7 is normal is set. You may switch it on.

After confirming the operation of the switching clutch 7 as shown in FIGS. 3 and 4, it is determined whether or not the switching clutch 7 is normal (step S4). That is, when the above-mentioned steps S304 and S324 are executed, a negative judgment is made in step S4, and when steps S311 and S331 are executed, a positive judgment is made in step S4.

If it is positively determined in step S4 because the switching clutch 7 is normal, the flag Fch that allows switching to the engine running mode is set to on (step S5), and this routine is temporarily terminated. On the contrary, if it is negatively determined in step S4 because the switching clutch 7 is abnormal, the flag Fch that allows switching to the engine running mode is set to off (step S6), and this routine is performed. Is closed once. That is, steps S5 and S6 are substantially the same steps as the above-mentioned steps S311 and S331, and steps S304 and S324.

The control device according to the embodiment of the present invention is configured to execute the control example shown in FIG. 5 in parallel with the control example shown in FIG. The control example shown in FIG. 5 is control when there is a request for switching between the engine running mode and the EV running mode, and first, it is determined whether or not the engine running mode is in progress (step S10). ). This step S10 can be determined by confirming the traveling mode determined based on the map stored in the ECU 21 described above, or is determined based on whether or not the switching clutch 7 is engaged. can do.

If it is positively determined in step S10 because the engine is in the engine traveling mode, it is determined whether or not there is a request for switching to the EV traveling mode (step S11). The request for switching to the EV driving mode in step S11 is a switch operation by the driver in addition to the request for switching the driving mode determined by control such as when the required driving force or the vehicle speed changes to the region for setting the EV driving mode. This includes the case where there is a request to switch the driving mode due to such reasons.

If a negative determination is made in step S11 because there is no request to switch to the EV driving mode, the engine driving mode is maintained (step S12), and this routine is temporarily terminated. On the contrary, when it is positively determined in step S11 due to the request for switching to the EV driving mode, for example, a predetermined condition such as whether or not the remaining charge of the battery is equal to or higher than a predetermined value. After confirming that is satisfied, the mode is switched to the series running mode (step S13), and this routine is temporarily terminated. In other words, the switching clutch 7 is switched to the series running mode as it is without confirming whether or not it operates normally.

On the other hand, if it is negatively determined in step S10 because it is in the EV driving mode, it is determined whether or not there is a request for switching to the engine driving mode (step S14), and the switching to the engine driving mode is performed. If it is negatively determined in step S14 because there is no request, the EV driving mode is maintained (step S15), and this routine is temporarily terminated. That is, the state in which the switching clutch 7 is released is maintained.

On the contrary, when a positive judgment is made in step S14 due to a request for switching to the engine driving mode, the above-mentioned steps S5 and S6 are not immediately executed without switching to the engine driving mode. Whether or not the flag Fch is turned on, that is, as a result of checking the operation of the switching clutch 7, it is determined whether or not switching of the engine running mode is permitted (step S16). Then, if it is positively determined in step S16 because the switch to the engine drive mode is permitted, the switch to the engine drive mode (step S17) is performed, and the switch to the engine drive mode is not permitted. If a negative determination is made in step S16, the EV traveling mode is maintained (step S15).

FIG. 6 shows changes in the state of switching the traveling mode, the state of checking the operation of the switching clutch 7, and the state of the flag Fok indicating that the switching clutch 7 is normal when the control example shown in FIGS. 2 to 5 is executed. is there. The solid line in FIG. 6 indicates the case where the switching clutch 7 operates normally, and the broken line indicates the case where the switching clutch 7 does not operate normally.

In the example shown in FIG. 6, the power supply of the vehicle 1 is stopped at t0, the ignition (IG) is turned on at t1 and the ready switch (RDY) is turned on at t2. At that point, the series running mode is set by stopping. As a result, the operation check of the switching clutch 7 is executed at the time t3 delayed from the time t2, and when the switching clutch 7 operates normally at the time t4 when the operation check of the switching clutch 7 is completed (solid line), the flag is flagged. If the Fok is switched on and does not operate normally (dashed line), the flag Fok remains off.

In that state, when the driver operates the driving mode changeover switch to switch to the engine driving mode (parallel driving mode) (at t5), when the switching clutch 7 operates normally (solid line). Is switched to the parallel driving mode, and if it does not operate normally (broken line), the series driving mode is maintained. If the switching clutch 7 does not operate normally and the driving mode is maintained contrary to the operation of the switching switch of the driver, the driver is informed by a warning sound or the like that the driving mode cannot be switched. It is preferable to transmit.

As described above, in the EV driving mode, more specifically, in the series driving mode, it is determined whether or not the switching clutch 7 operates normally, and the switching clutch 7 is operated on the condition that the switching clutch 7 operates normally. Since the vehicle is engaged and switched to the engine running mode, the switching clutch 7 can be appropriately released when some failure occurs in the vehicle 1 after switching to the engine running mode. Further, the rear transmission mechanism 8 provided in series with the switching clutch 7 is configured to be able to switch to the neutral state when the engine 2 is stopped, so that the switching clutch 7 may not operate normally. However, by switching the rear transmission mechanism 8 to the neutral state and checking the operation of the switching clutch 7, the engine torque is unintentionally transmitted to the drive wheels (rear wheels 5) in the EV driving mode. Can be prevented. Therefore, it is possible to prevent the driver from feeling uncomfortable when checking the operation of the switching clutch 7. Further, in the series running mode, the engine 2 is driven. Therefore, it is not necessary to drive the stopped engine 2 in order to confirm the operation of the switching clutch 7, and it is possible to prevent the driver from feeling uncomfortable.

Further, the control device according to the embodiment of the present invention is not limited to the one that executes the operation check of the switching clutch 7 in the EV running mode, and checks the operation of the switching clutch 7 in the transitional period of switching from the engine running mode to the EV running mode. You may do it. A flowchart for explaining the control example is shown in FIG. The control flow shown in FIG. 7 is configured to confirm the operation of the switching clutch 7 during the transitional period of switching from the parallel traveling mode to the series traveling mode. In other words, the release operation of the switching clutch 7 in order to switch the traveling mode from the parallel traveling mode to the series traveling mode is also configured to be a part of the operation confirmation of the switching clutch 7.

Therefore, in the example shown in FIG. 7, first, it is determined whether or not the parallel traveling mode is set (step S21), and when the parallel traveling mode is set and the determination is positive in step S22, the case is determined. , It is determined whether or not there is a request to switch to the series running mode (step S22). This step S21 can be determined by confirming the traveling mode determined based on the map stored in the ECU 21 described above, whether or not the switching clutch 7 is engaged, or the front motor. It can be determined based on whether or not the 4 is energized. Further, in step S22, it is determined whether or not there is a request for switching to the series driving mode based on the required driving force, the vehicle speed, the remaining charge of the battery, or the like, and the switching to the series driving mode is performed based on the switch operation by the driver. Whether or not there is a request can be determined.

If it is positively determined in step S22 due to the request for switching to the series running mode, the operation check of the switching clutch 7 is executed (step S23). The operation check of the switching clutch 7 may be performed in the same manner as in the control examples shown in FIGS. 3 and 4. On the other hand, in the control example shown in FIGS. 3 and 4, the operation of the switching clutch 7 is confirmed from the state in which the switching clutch 7 is not supplied with oil, whereas in this step S24, the switching clutch 7 has already been checked. Check the operation from the state where the oil supply is supplied to the clutch. Therefore, in step S24, for example, after reducing the original pressure and the control pressure, it may be executed in the same manner as the control example shown in FIGS. 3 and 4. Alternatively, first, after releasing the rear transmission mechanism 8, the control valve 13 is controlled to the control pressure at which the switching clutch 7 is in the released state to determine whether or not the control pressure has dropped to the target pressure, and then, The control valve 13 is controlled so as to increase the control pressure again to determine whether or not the control pressure has increased to the target pressure, and then the control pressure and the original pressure are decreased to release the switching clutch 7. The control valve 13 and the regulator valve 12 may be controlled so as to control the control valve 13 and the regulator valve 12 to determine whether or not the control pressure and the original pressure have dropped to the target pressure. That is, the order in which the operation of the switching clutch 7 is checked may be changed as appropriate. Whether or not the switching clutch 7 operates normally may be determined based on a change in the input rotation speed or the like as shown in FIG. Further, if it is negatively determined in either step S21 or step S22, this routine is temporarily terminated as it is.

Then, similarly to steps S4 to S6 shown in FIG. 2, it is determined whether or not the switching clutch 7 is normal (step S24), and if the switching clutch 7 is normal, switching to the engine running mode is performed. The flag Fch that allows switching to the engine running mode is set to on (step S25), and if the switching clutch 7 is abnormal, the flag Fch that allows switching to the engine running mode is set to off (step S26). Exit the routine once.

By checking the operation of the switching clutch 7 in the process of switching from the engine running mode (parallel running mode) to the EV running mode (series running mode) as described above, the switching clutch 7 for switching from the engine running mode to the EV running mode The release operation of the switching clutch 7 can be included in the operation check of the switching clutch 7, and as a result, the time for checking the operation of the switching clutch 7 can be shortened.

The operation check of the switching clutch 7 in the embodiment of the present invention is not limited to the period in which the above series driving mode is set or the transitional period in which the engine driving mode is switched to the EV driving mode. When the required driving force is reduced to the extent that the vehicle 1 is coasted while the vehicle is being set, or when the required driving force is reduced to a driving force that can be satisfied only by the driving torque of the front motor 4. The operation check of the switching clutch 7 may be executed.

1 Hybrid vehicle 2 Engine 3 Rear motor 4 Front motor 5 Rear wheel 6 Front wheel 7 Switching clutch 8 Rear transmission mechanism 11 Oil pump 12 Regulator valve 13 Control valve 21 Electronic control unit (ECU)

Claims (1)

An internal combustion engine, a generator connected so as to be able to transmit torque to a rotating member provided in a path for transmitting torque from the internal combustion engine to the drive wheels, and the internal combustion engine and the drive on the drive wheel side of the rotating member. It has a clutch mechanism that cuts off the transmission of torque to and from the wheels, and an electric motor that is connected to the drive wheels or other drive wheels different from the drive wheels so that torque can be transmitted.
The clutch mechanism is engaged with the first traveling mode in which the clutch mechanism is released, the power of the internal combustion engine is converted into electric power by the generator, and the power is output from the electric motor to travel. In a control device for a hybrid vehicle provided with a drive system capable of setting a second travel mode in which the drive torque of the internal combustion engine is transmitted to the drive wheels to travel.
A controller for controlling the drive system is provided.
The controller
It is determined whether or not the engagement operation for engaging the clutch mechanism and the release operation for releasing the clutch mechanism are possible.
A hybrid characterized in that it is configured to allow switching from the first traveling mode to the second traveling mode when it is determined that the engaging operation and the disengaging operation of the clutch mechanism are possible. Vehicle control device.

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