JP4529130B2 - Vehicle control device - Google Patents

Description

  The present invention relates to a control apparatus for a vehicle in which a generator generates power (decelerated regenerative power generation) while performing slip control of a lockup clutch during a fuel cut period during deceleration.

  In general, an automatic transmission mounted on a vehicle has a transmission gear mechanism connected to a crankshaft of an engine via a torque converter, and a pump impeller (input shaft) and a turbine runner (output shaft) of the torque converter in a predetermined operation region. In many cases, the transmission efficiency of the automatic transmission is improved by directly connecting the motor with a lock-up clutch.

  In a vehicle equipped with such an automatic transmission with a lockup clutch, for example, as described in Patent Document 1 (Japanese Patent Laid-Open No. 5-180331), the output shaft rotational speed ( The slip amount of the lockup clutch (hereinafter referred to as “L / U slip amount”), which is the difference between the turbine rotational speed) and the input shaft rotational speed (engine rotational speed), is made to coincide with the target L / U slip amount. By performing L / U slip control that controls the engagement force of the lockup clutch, the period until the engine speed drops below the fuel cut return speed without deteriorating the idling feeling during deceleration (that is, during deceleration) There is one that expands the period during which fuel cut is carried out to improve fuel efficiency.

Further, as described in Patent Document 2 (Japanese Patent Laid-Open No. 11-107805), deceleration regeneration that generates power by driving a generator (alternator) using deceleration energy of a vehicle during a fuel cut period during deceleration. There is one in which deceleration energy of a vehicle is efficiently converted into electric energy and collected in a battery by performing power generation.
Japanese Patent Laid-Open No. 5-180331 (second page, etc.) JP-A-11-107805 (2nd page, FIG. 6 etc.)

  In recent years, for the purpose of further improving fuel efficiency, it has been studied to execute the L / U slip control described above in combination with the deceleration regenerative power generation during the fuel cut period during deceleration.

  However, during the fuel cut during deceleration, the throttle opening (accelerator opening) is fully closed and the engine torque is small. Therefore, as shown in FIG. When the generator is driven with engine torque while performing U / U slip control, the engine rotation speed rapidly decreases due to the power generation torque of the generator even in a deceleration state where the vehicle speed (turbine rotation speed) decreases relatively slowly. A phenomenon occurs (because the L / U slip amount increases rapidly). As a result, even in the deceleration state in which the vehicle speed decreases relatively slowly, the engine rotation speed is quickly reduced below the fuel cut return rotation speed by the deceleration regenerative power generation, and the fuel cut period during deceleration is shortened. There is a problem that not only the fuel efficiency improvement effect due to the fuel cut during deceleration is reduced, but also the deceleration regenerative power generation period is shortened and the deceleration energy recovery efficiency (and hence the fuel efficiency improvement effect) due to the deceleration regenerative power generation is also reduced. In particular, there is a tendency to install a generator with a large amount of power generation in accordance with the recent trend of increasing the electric load of vehicles, and since the power generation torque of the generator also increases with the increase in power generation amount of this generator, the above-mentioned These problems tend to become larger.

  The present invention has been made in view of such circumstances. Accordingly, the object of the present invention is to execute an internal combustion engine while executing a combination of L / U slip control and deceleration regenerative power generation during a fuel cut during deceleration. It is possible to lengthen both the fuel cut period during deceleration and the deceleration regenerative power generation period by preventing a sudden decrease in the engine speed, and the fuel efficiency can be effectively improved by the L / U slip control and the deceleration regenerative power generation. It is in providing the control apparatus of a vehicle.

In order to achieve the above object, the invention according to claim 1 is directed to a system that executes a combination of L / U slip control and deceleration regenerative power generation during a fuel cut period during deceleration. in which regenerative power generation is to be controlled to be smaller than the L / U slip amount when decelerating regenerative power generation L / U slip amount is not performed in accordance with the deceleration state during deceleration fuel cut period is performed.

As described above, in the deceleration fuel cut-off period the deceleration regeneration is performed, usually by running the same L / U slip control and (when decelerating regenerative power generation is not performed), the output shaft rotational speed of the vehicle speed (torque converter ) Decreases relatively slowly, the L / U slip amount increases rapidly due to the power generation torque of the generator, and the rotational speed of the internal combustion engine decreases rapidly. Therefore, the fuel cut period during deceleration and the deceleration regenerative power generation The period will be shortened. Focusing on this characteristic, the present invention is less controlled than according to the deceleration state during deceleration fuel cut-off period the deceleration regeneration is performed L / U slip amount normally (when a deceleration regenerative power generation is not performed) To do. In this way, the L / U slip amount is controlled to be smaller than usual even when the generator is driven and the deceleration regenerative power generation is performed while performing the L / U slip control during the fuel cut period during deceleration. Therefore, a rapid decrease in the rotational speed of the internal combustion engine (input shaft rotational speed of the torque converter) is suppressed by the deceleration energy of the vehicle (output shaft rotational speed of the torque converter). As a result, while performing a combination of L / U slip control and deceleration regenerative power generation during the fuel cut period during deceleration, a sudden decrease in the rotational speed of the internal combustion engine can be prevented to reduce the fuel cut period during deceleration and the deceleration regenerative power generation period. The fuel efficiency can be effectively improved by the L / U slip control and the deceleration regenerative power generation.

  In this case, as in claim 2, it is preferable to set the target L / U slip amount to decrease as the rotational speed of the internal combustion engine or the output shaft rotational speed of the torque converter or the vehicle speed decreases during the fuel cut period during deceleration. . By doing so, the L / U slip amount is controlled to decrease as the rotational speed of the internal combustion engine and the deceleration energy of the vehicle (output shaft rotational speed and vehicle speed of the torque converter) decrease, so the fuel cut during deceleration Until the deceleration energy of the vehicle decreases to a level at which deceleration regenerative power generation cannot be performed during the period, the engine rotation speed can be maintained at the fuel cut return rotation speed or higher by the vehicle deceleration energy. Thereby, it becomes possible to continue the deceleration regenerative power generation until the deceleration energy of the vehicle decreases to a level at which the deceleration regenerative power generation cannot be performed, and the deceleration energy of the vehicle can be used most efficiently to perform the regenerative power generation. The maximum fuel efficiency improvement effect can be obtained.

  By the way, if the L / U slip amount is reduced in a region where the rotational speed of the internal combustion engine and the deceleration energy of the vehicle are high during the deceleration operation, the decrease in the rotational speed of the internal combustion engine during the deceleration operation becomes too slow and the driver during the deceleration operation. There is a concern that the ability will decrease.

As a countermeasure, the target L / U slip amount is set until the rotational speed of the internal combustion engine or the output shaft rotational speed of the torque converter or the vehicle speed falls below a predetermined value during the fuel cut period during deceleration as in claim 3. You may make it set to the same target L / U slip amount as usual (when deceleration regeneration power generation is not performed) . In this way, even during the fuel cut during deceleration, when the rotational speed of the internal combustion engine or the deceleration energy of the vehicle is high, the same L / U slip control as when normal ( when deceleration regenerative power generation is not performed) is performed. To maintain good drivability during deceleration operation.

  In the present invention, the deceleration regenerative power generation may be terminated simultaneously with the return (end) of the fuel cut during deceleration. However, if the generator is continuously driven in the low rotation region near the fuel cut return rotational speed, Because the power generation torque is large, the rotational speed of the internal combustion engine rapidly decreases in the low rotation range near the fuel cut return rotation speed, the fuel cut return timing at deceleration arrives earlier, and the fuel cut period at deceleration decreases. There is a concern that the rotational speed of the internal combustion engine falls too much and drivability deteriorates.

  As a countermeasure, the regenerative regeneration power generation ends when the rotational speed of the internal combustion engine falls to the power generation end rotational speed set slightly higher than the fuel cut return rotational speed during the fuel cut period during deceleration as in claim 4 Then, the lockup clutch may be released when deceleration regenerative power generation ends during the fuel cut period during deceleration. In this way, the rotational speed of the internal combustion engine can be gradually reduced in the low rotational speed region near the fuel cut return rotational speed, the fuel cut period during deceleration can be extended, and a drop in the rotational speed of the internal combustion engine can be prevented. There is an advantage that drivability can be improved.

Hereinafter, an embodiment embodying the best mode for carrying out the present invention will be described.
First, a schematic configuration of the entire system will be described with reference to FIG. An intake pipe 12 of an engine 11 that is an internal combustion engine is provided with a throttle valve 13 whose opening is adjusted by a motor or the like, and a throttle opening sensor 14 that detects the throttle opening. Further, the surge tank 15 provided on the downstream side of the throttle valve 13 is provided with an intake manifold 16 for introducing air into each cylinder of the engine 11, and fuel is supplied to the vicinity of the intake port of the intake manifold 16 of each cylinder. A fuel injection valve 17 for injection is attached.

  In the automatic transmission 18, the input shaft 21 of the torque converter 20 is connected to the crankshaft 19 of the engine 11, and the transmission gear mechanism 23 is connected to the output shaft 22 of the torque converter 21. Inside the torque converter 20, a pump impeller 24 and a turbine runner 25 constituting a fluid coupling are provided facing each other, and a stator 26 that rectifies the flow of oil is provided between the pump impeller 24 and the turbine runner 25. It has been. The pump impeller 24 is connected to the input shaft 21 of the torque converter 20, and the turbine runner 25 is connected to the output shaft 22 of the torque converter 20.

  The torque converter 20 is provided with a lockup clutch 27 for bringing the input shaft 21 side and the output shaft 22 side into a direct connection state. The output torque of the engine 11 is transmitted to the transmission gear mechanism 23 via the torque converter 20, and is shifted by a plurality of gears of the transmission gear mechanism 23 and transmitted to the drive shaft of the wheel.

  The engine 11 is provided with an engine rotation speed sensor 28 that detects an engine rotation speed Ne (= input shaft rotation speed of the torque converter 20), and the automatic transmission 18 includes a turbine that is the output shaft rotation speed of the torque converter 20. A turbine rotation speed sensor 29 that detects a rotation speed Nt (rotation speed of the turbine runner 25) is provided. Further, the brake operation is detected by the brake switch 30, and the vehicle speed is detected by the vehicle speed sensor 31.

  On the other hand, the rotation of the crank pulley 33 connected to the crankshaft 19 is transmitted to the generator 32 (alternator) via the belt 34, and the generator 32 is rotationally driven by the power of the crankshaft 19 to generate power. It has become.

  Outputs of the various sensors described above are input to a control circuit (hereinafter referred to as “ECU”) 35. The ECU 35 is composed of one or a plurality of microcomputers that comprehensively control the engine 11 and the automatic transmission 18, and executes various engine control programs (not shown) to respond to engine operating conditions. By controlling the fuel injection amount of the fuel injection valve 17 and the ignition timing of the ignition plug (not shown) and executing a shift control program (not shown), the shift lever is operated according to the operating range and operating conditions. The hydraulic control circuit 36 of the automatic transmission 18 is controlled to switch the gear ratio of the transmission gear mechanism 23.

The ECU 35 also functions as an L / U slip control unit and a power generation control unit by executing the routines shown in FIGS. 2 to 5 described later, and drives the generator 32 during the fuel cut period during deceleration. While decelerating regenerative power generation, the engagement force of the lock-up clutch 27 is controlled, and the lock-up that is the difference between the output shaft rotational speed (turbine rotational speed Nt) and the input shaft rotational speed (engine rotational speed Ne) of the torque converter 20 L / U slip control is performed to control the slip amount of the clutch 27 (hereinafter referred to as “L / U slip amount”), and the L / U slip amount is normally set in accordance with the deceleration state during the fast fuel cut period. by controlling smaller than (when decelerating regenerative power generation is not performed), the deceleration regeneration period and the deceleration fuel cut-off period to prevent the sudden decrease in the engine rotational speed Ne Kusuru.

  In the comparative example shown in FIG. 8, the generator 32 is driven to perform decelerating regenerative power generation while performing L / U slip control with the same target L / U slip amount (for example, 50 rpm) as usual during the decelerating regenerative power generation period. I have to. In this comparative example, even in a deceleration state in which the vehicle speed (turbine rotation speed) decreases relatively slowly, a phenomenon occurs in which the engine rotation speed rapidly decreases due to the power generation torque of the generator 32. This is because the target L / U slip amount is set to a relatively large value (for example, 50 rpm) that is the same as usual, and therefore when the power generation torque of the generator 32 is applied, the L / U slip amount increases rapidly. A phenomenon in which the engine speed rapidly decreases due to the sudden increase in the L / U slip amount occurs. As a result, even in the deceleration state in which the vehicle speed decreases relatively slowly, the engine rotation speed is quickly reduced below the fuel cut return rotation speed by the deceleration regenerative power generation, and the fuel cut period during deceleration is shortened. There is a problem that not only the fuel efficiency improvement effect due to the fuel cut during deceleration is reduced, but also the deceleration regenerative power generation period is shortened and the deceleration energy recovery efficiency (and hence the fuel efficiency improvement effect) due to the deceleration regenerative power generation is also reduced. In particular, there is a tendency to mount a generator 32 with a large power generation amount in accordance with the recent trend of increasing the electric load of the vehicle, and the power generation torque of the generator 32 increases with the increase in the power generation amount of the power generator 32. For this reason, the above-mentioned problems tend to increase.

  On the other hand, in the present embodiment, as shown in FIG. 9, the target L / U slip amount is set to a value smaller than normal (for example, 10 rpm) in accordance with the deceleration state during the deceleration regenerative power generation period. While performing U-slip control, the generator 32 is driven to perform decelerated regenerative power generation. Thus, if the target L / U slip amount is made smaller than usual during the deceleration regenerative power generation period, the L / U slip control can be performed while the generator 32 is driven and the decelerating regenerative power generation is performed. Since the U-slip amount is controlled to be smaller than usual, a sudden decrease in the engine rotational speed (the input shaft rotational speed of the torque converter 32) can be suppressed by the deceleration energy of the vehicle (the output shaft rotational speed of the torque converter 32). As a result, while the L / U slip control and the deceleration regenerative power generation are executed in combination during the fuel cut period during deceleration, the engine speed is prevented from suddenly decreasing and the fuel cut period during deceleration and the deceleration regenerative power generation period are lengthened. The fuel efficiency can be effectively improved by the L / U slip control and the deceleration regenerative power generation.

According to the test results of the present inventor, when the vehicle is decelerated from a vehicle speed of 60 km / h, when the regenerative power generation is performed with the target L / U slip amount set to 50 rpm as in the comparative example (FIG. 8), the generated current When the power generation current is 100 A, the deceleration regenerative power generation period is about 2 sec. When the power generation current is 100 A, the deceleration regenerative power generation period is about 4 sec. When the power generation current is 90 A, the deceleration regenerative power generation period is about 8 sec. As in the example (FIG. 9), when the target L / U slip amount is set to 10 rpm, which is a normal 1 / L L / U slip amount, and decelerated regenerative power generation is performed, the decelerated regenerative power is generated when the generated current is 120A. When the power generation period is about 4 seconds and the generated current is 100 A, the deceleration regenerative power generation period is about 10 seconds, and when the power generation current is 90 A, the deceleration regenerative power generation period is about 25 seconds. As is apparent from the test results, in this example, it was found that the deceleration regenerative power generation period can be extended more than twice that of the comparative example.
Hereinafter, the processing content of each routine of FIG. 2 thru | or FIG. 5 which ECU35 performs is demonstrated.

[Main routine]
The main routine of FIG. 2 is executed at a predetermined cycle (for example, 4 ms cycle) during the ON period of the ignition switch. When this routine is started, first, at step 101, a deceleration determination routine of FIG. 3 described later is executed to determine the deceleration state from the driving state of the vehicle. Thereafter, the routine proceeds to step 102, where an L / U control switching routine shown in FIG. 4 described later is executed, and the L / U control is switched according to the deceleration state determined at step 101 and the engine rotational speed Ne.

  Thereafter, the routine proceeds to step 103, where a target L / U slip amount calculation routine of FIG. 5 described later is executed, and the output shaft rotational speed (turbine rotational speed Nt) of the torque converter 20 and the input shaft rotational speed (engine rotational speed Ne). ), The target value of the slip amount of the lockup clutch 27 (target L / U slip amount) is calculated.

  In the next step 104, an actual L / U slip control process is executed so that the actual L / U slip amount (Nt-Ne) matches the target L / U slip amount calculated in step 103. The engagement force of the lockup clutch 27 is controlled. Thereafter, the process proceeds to step 105, and a process of generating power by supplying a control current to the generator 32 is performed.

[Deceleration judgment routine]
The deceleration determination routine of FIG. 3 is a subroutine executed in step 101 of FIG. When this routine is started, it is first determined in step 201 whether or not the throttle is fully closed. If the throttle is not fully closed, it is determined that the throttle is not decelerated (constant speed running or acceleration), and step 203 is executed. Then, the strong deceleration flag XS is set to “0”, and in the next step 204, the weak deceleration flag XM is set to “0”, and this routine is finished. Thus, setting the strong deceleration flag XS = 0 and the weak deceleration flag XM = 0 indicates that the vehicle is in a non-deceleration state (constant speed running or acceleration state).

  If it is determined in step 201 that the throttle is fully closed, the process proceeds to step 202, where it is determined whether the brake is depressed (whether the brake switch 30 is ON), and if the brake is depressed. When the throttle is fully closed, it is determined that the vehicle is decelerated by depressing the brake, and the process proceeds to step 205 where the strong deceleration flag XS is set to “1”. In the next step 206, the weak deceleration flag XM is set to “1”. Set to 0 "to end this routine. As described above, the strong deceleration flag XS = 1 and the weak deceleration flag XM = 0 are set to indicate that the vehicle is in the strong deceleration state.

  On the other hand, if it is determined in step 202 that the brake is not depressed, it is determined that the vehicle is decelerating without fully depressing the brake when the throttle is fully closed. The flag XS is set to “0”, and in the next step 208, the weak deceleration flag XM is set to “1”, and this routine is finished. Thus, setting the strong deceleration flag XS = 0 and the weak deceleration flag XM = 1 indicates that the vehicle is in the weak deceleration state.

[L / U control switching routine]
The L / U control switching routine in FIG. 4 is a subroutine executed in step 102 in FIG. When this routine is started, first, at step 301, it is determined whether or not the engine speed Ne is higher than a predetermined value γ. Here, the predetermined value γ is set to a value that changes in accordance with the driving state of the vehicle. If it is determined that the engine rotation speed Ne is equal to or less than the predetermined value γ, it is determined that the operation state is not lockable up, the process proceeds to step 305, the L / U flag XLU is set to “0”, and the next In step 306, the L / U slip flag XSLU is set to “0”. As a result, the lockup clutch 27 is released.

  If it is determined in step 301 that the engine rotational speed Ne is higher than the predetermined value γ, the process proceeds to step 302 to determine whether or not the weak deceleration flag XM is “1”. If it is “1”, it is determined that the vehicle is weakly decelerating (there is no possibility of engine stall due to sudden braking), and the process proceeds to step 303 where the L / U flag XLU is set to “0”. The U slip flag XSLU is set to “1”. Thereby, it switches to the L / U slip control at the time of deceleration (at the time of deceleration regeneration power generation).

  If it is determined in step 302 that the weak deceleration flag XM is “0”, the process proceeds to step 307 to determine whether or not the strong deceleration flag XS is “1”, and the strong deceleration flag XS is “1”. "", It is determined that the vehicle is in a strong deceleration state (there is a possibility of engine stall due to sudden braking), the process proceeds to step 308, the L / U flag XLU is set to "0", and in the next step 309, L / U The slip flag XSLU is set to “0”. As a result, the lockup clutch 27 is released.

  On the other hand, if the strong deceleration flag XS is determined to be “0” in step 307, the weak deceleration flag XM is also determined to be “0” in step 302. It is determined that the vehicle is traveling at a high speed or in an accelerated state, and the process proceeds to step 310 to perform normal L / U control.

[Target L / U slip amount calculation routine]
The target L / U slip amount calculation routine of FIG. 5 is a subroutine executed in step 103 of FIG. When this routine is started, first, in step 401, the target L / U slip amount at the normal time is calculated using the map of FIG. The normal target L / U slip amount is set to a constant value (for example, 50 rpm) in the entire rotation region.

  Thereafter, the process proceeds to step 402, where it is determined whether or not the L / U slip flag XSLU is “1”. If the L / U slip flag XSLU is “0”, the L / U slip control is not performed. Therefore, this routine is terminated without performing the subsequent processing.

  If it is determined in step 402 that the L / U slip flag XSLU is “1”, the process proceeds to step 403 to determine whether or not the engine speed Ne is higher than a predetermined value β. Here, the predetermined value β is set to the lowest engine speed (for example, 850 rpm) at which the generator 32 can decelerate and regenerate. This predetermined value β is set slightly higher than the fuel cut return rotational speed (for example, 800 rpm).

  If it is determined in step 403 that the engine rotation speed Ne is higher than the predetermined value β (deceleration regeneration power generation rotation speed), it is determined that deceleration regeneration power generation is possible, the process proceeds to step 404, and the deceleration regeneration power generation flag XGEN is set. In the next step 405, the target L / U slip amount at the time of deceleration regenerative power generation is calculated from the map of FIG.

  The target L / U slip amount at the time of the deceleration regenerative power generation calculated by the map of FIG. 7 is set to a value smaller than the normal time (FIG. 6), and further, the turbine rotational speed Nt (output shaft rotation) of the torque converter 20 is set. It is set so that the target L / U slip amount decreases as the speed) decreases. In this way, since the L / U slip amount is controlled to decrease as the vehicle deceleration energy (turbine rotational speed Nt or vehicle speed) decreases, the vehicle deceleration energy is reduced during the fuel cut period during deceleration. Until the engine power decreases to a level at which regenerative power generation cannot be performed, the engine rotational speed Ne can be maintained at a predetermined value β (decelerated regenerative power generation end rotational speed) or more by the deceleration energy of the vehicle. Thereby, it becomes possible to continue the deceleration regenerative power generation until the deceleration energy of the vehicle decreases to a level at which the deceleration regenerative power generation cannot be performed, and the deceleration energy of the vehicle can be used most efficiently to perform the regenerative power generation. The maximum fuel efficiency improvement effect can be obtained.

  However, if the L / U slip amount is reduced in a region where the vehicle speed (vehicle deceleration energy) is high during deceleration operation, the decrease in the engine rotation speed Ne during deceleration operation becomes too slow and drivability during deceleration operation decreases. There are concerns. As a countermeasure, in the map of FIG. 7, the target L / U slip amount is set to the same target L / U slip amount (for example, 50 rpm) until the turbine rotation speed Nt decreases to a predetermined value or less during the fuel cut period during deceleration. It is set to. In this way, even during the fuel cut during deceleration, when the vehicle speed (vehicle deceleration energy) is high, the same L / U slip control as usual is performed to improve drivability during deceleration operation. Can be maintained.

  In the map of FIG. 7, the target L / U slip amount during deceleration regenerative power generation is set using the turbine rotational speed Nt (output shaft rotational speed) of the torque converter 20 as a parameter, but the engine rotational speed Ne or vehicle speed is set. May be used as a parameter to set the target L / U slip amount during deceleration regenerative power generation. In short, the target L / U slip amount during deceleration regenerative power generation may be set according to the deceleration energy of the vehicle. It ’s fine.

  On the other hand, if it is determined in step 403 that the engine rotational speed Ne is equal to or lower than the predetermined value β (deceleration regeneration power generation rotational speed), the process proceeds to step 406 where the deceleration regeneration power generation flag XGEN is set to “0” and deceleration regeneration is performed. End power generation.

  According to the present embodiment described above, while performing the L / U slip control while setting the target L / U slip amount to a value smaller than normal (for example, 10 rpm) according to the deceleration state during the deceleration regenerative power generation period, Since the generator 32 is driven to perform decelerating regenerative power generation, even if the generator 32 is driven to perform decelerating regenerative power generation while performing L / U slip control during decelerating operation, the L / U slip amount is not increased. It is controlled to be smaller than usual, and a rapid decrease in the engine rotational speed (the input shaft rotational speed of the torque converter 32) is suppressed by the deceleration energy of the vehicle (the output shaft rotational speed of the torque converter 32). As a result, while the L / U slip control and the deceleration regenerative power generation are executed in combination during the fuel cut period during deceleration, the engine speed is prevented from suddenly decreasing and the fuel cut period during deceleration and the deceleration regenerative power generation period are lengthened. The fuel efficiency can be effectively improved by the L / U slip control and the deceleration regenerative power generation.

  In the present invention, the deceleration regenerative power generation may be terminated simultaneously with the return (end) of the fuel cut during deceleration, but if the generator 32 is continuously driven in the low rotation region near the fuel cut return rotational speed, Since the power generation torque of the generator 32 is large, the engine rotation speed rapidly decreases in the low rotation region near the fuel cut return rotation speed, the fuel cut return timing at the time of deceleration arrives earlier, and the fuel cut period at the time of deceleration becomes shorter. There is a concern that drivability will deteriorate due to excessive engine speed reduction.

  As a countermeasure, in this embodiment, as shown in FIG. 9, the deceleration regenerative power generation end rotational speed (predetermined value β) in which the engine rotational speed is set slightly higher than the fuel cut return rotational speed during the fuel cut period during deceleration. The deceleration regenerative power generation is terminated when the speed is reduced to the lower limit, and the lockup clutch 27 is released when the deceleration regenerative power generation is completed during the fuel cut period during deceleration. There is an advantage that the engine speed can be lowered gradually, the fuel cut period during deceleration can be extended, the engine speed can be prevented from dropping, and the drivability can be improved.

It is a schematic block diagram of the whole system in one Example of this invention. It is a flowchart which shows the flow of a process of a main routine. It is a flowchart which shows the flow of a process of a deceleration determination routine. It is a flowchart which shows the flow of a process of L / U control switching routine. It is a flowchart which shows the flow of a process of target L / U slip amount calculation routine. It is a figure which shows notionally an example of the map of the target L / U slip amount at the normal time. It is a figure which shows notionally an example of the map of the target L / U slip amount at the time of deceleration regeneration electric power generation. It is a time chart explaining the example of control at the time of the deceleration regeneration power generation of a comparative example. It is a time chart explaining the example of control at the time of the deceleration regenerative power generation of one Example of this invention. It is a characteristic view showing the relationship between the deceleration regenerative power generation period, the generated current, and the target L / U slip amount.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 11 ... Engine (internal combustion engine), 12 ... Intake pipe, 13 ... Throttle valve, 17 ... Fuel injection valve, 18 ... Automatic transmission, 19 ... Crankshaft, 20 ... Torque converter, 21 ... Input shaft, 22 ... Output shaft, DESCRIPTION OF SYMBOLS 23 ... Transmission gear mechanism, 24 ... Pump impeller, 25 ... Turbine runner, 26 ... Stator, 27 ... Lock-up clutch, 28 ... Engine rotational speed sensor, 29 ... Turbine rotational speed sensor, 32 ... Generator, 35 ... ECU (L / U slip control means, power generation control means)

Claims (4)

A generator driven by the power of the internal combustion engine, a lockup clutch that directly connects the input shaft side and the output shaft side of the torque converter of the automatic transmission, and a slip amount of the lockup clutch during deceleration operation (hereinafter referred to as “ In a vehicle control device comprising L / U slip control means for controlling (L / U slip amount))
Comprising power generation control means for performing decelerating regenerative power generation by the generator during fuel cut during deceleration ;
The L / U slip control means determines an L / U slip amount according to a deceleration state during a fuel cut period during deceleration during which the deceleration regenerative power generation is performed from an L / U slip amount when the deceleration regenerative power generation is not performed. A control device for a vehicle, characterized in that the control is small. Set to the L / U slip control means decreases the target L / U slip amount according to the rotational speed or output shaft speed or vehicle speed of the torque converter of the internal combustion engine during the deceleration fuel cut-off period is lower The vehicle control device according to claim 1. The L / U slip control means, the target L / U slip amount to the rotational speed or the output shaft speed or vehicle speed of the torque converter of the internal combustion engine during the deceleration fuel cut-off period falls below a predetermined value 3. The vehicle control device according to claim 1, wherein the target L / U slip amount is set to be the same as that when the deceleration regeneration power generation is not performed . The power generation control unit, the ends of the power generation of the generator when the rotational speed of the internal combustion engine during the deceleration fuel cut-off period is decreased power up finish rotational speed set slightly higher than the fuel cut return rotational speed ,
The L / U slip control means according to any one of claims 1 to 3, characterized in that releasing the lockup clutch when the power generation is terminated in the generator during the deceleration fuel cut-off period Vehicle control device.

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