JP2012001087A - Apparatus for control of vehicle drive device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an apparatus for control of a vehicle drive device capable of preventing drop in drive force that may occur when releasing setting of an engine lower limit rotation speed in the vehicle drive device including a differential mechanism which constitutes part of a power transmission path between an engine and a driving wheel and whose differential state is controlled by a first electric motor.SOLUTION: A manual shift mode controller 108 sets an engine lower limit rotation speed NLe when a prescribed manual shift mode selection operation is performed. When releasing the setting of the engine lower limit rotation speed NLe to reduce an engine rotation speed Ne, a rotation speed slow change operation is executed, which reduces the engine rotation speed Ne more slowly than an engine rotation speed change gradient ΔNe. The inertia generated in response to rotation acceleration of a first electric motor M1 approaches zero, as the change of the engine rotation speed Ne becomes slower as compared with the case when the rotation speed slow change processing is not executed. Accordingly, the drop in drive force is prevented to reduce the sense of incongruity arising therefrom.

Description

  The present invention relates to a technique for controlling engine rotation speed while a vehicle is traveling.

  2. Description of the Related Art Conventionally, there has been proposed a control device for a vehicle drive device that alleviates a shock that may occur due to switching of the running state of the vehicle. For example, this is the engine brake control device disclosed in Patent Document 1. The vehicle disclosed in Patent Document 1 includes a continuously variable transmission between an engine and driving wheels, and the engine brake control device, which is a control device for the vehicle, is based on the throttle opening and the vehicle speed. In addition to the automatic shift range for performing automatic shifting of the continuously variable transmission, a manual shift range for performing upshift or downshift of the continuously variable transmission by operating a manual shift command means such as a paddle switch is provided. When the engine is in a no-load operation state (accelerator off) during traveling in the automatic shift range, the engine brake control device lowers the continuously variable transmission in response to a downshift operation of the manual shift command means. On the other hand, when the engine is switched from the no-load operation state to the load operation state (accelerator on) while a certain time has elapsed, the continuously variable transmission is returned to the gear ratio based on the throttle opening and the vehicle speed. Upshift to During the upshift, the engine brake control device reduces the shock by reducing the change in the gear ratio.

JP 2006-022913 A JP 2009-248801 A JP 2008-115964 A JP 2007-120703 A

  Although the vehicle disclosed in Patent Document 1 has only an engine as a driving power source for traveling, a vehicle driving device for a hybrid vehicle including an electric motor in addition to the engine as a driving power source for traveling is often used. Are known. For example, a vehicle drive device of the hybrid vehicle includes a differential mechanism that constitutes a part of a power transmission path between an engine and a drive wheel and that controls a differential state by a differential motor. The control device of the vehicle drive device controls the engine rotation speed along the preset engine operation curve without being restricted by the vehicle speed by controlling the differential state. Some of the control devices set an engine lower limit rotation speed when a predetermined manual setting operation is performed by an occupant. For example, when the control device has a function of selecting a travel range corresponding to the manual shift range, and the paddle switch is operated by an occupant and a travel range corresponding to the manual shift range is selected, The engine lower limit rotation speed is set. When the engine lower limit rotation speed is set, the occupant can increase the engine rotation speed beyond the engine lower limit rotation speed. For example, the occupant increases the engine rotation speed by the manual setting operation and Acceleration responsiveness when stepping on can be improved.

  Here, when the engine lower limit rotational speed is set, a decrease in the engine rotational speed is limited by the engine lower limit rotational speed. Therefore, when the setting of the engine lower limit rotational speed is canceled, the engine rotational speed is set. May decline rapidly. If the engine rotational speed decreases rapidly in this way, the rotational speed of the differential motor also changes through a change in the differential state of the differential mechanism as the engine rotational speed decreases. If the rotational speed of the differential motor changes, an inertia corresponding to the rotational acceleration is generated, and a part of the direct torque output from the differential mechanism toward the drive wheel by the inertia of the differential motor. Is canceled, and a driving force drop occurs in which the driving force temporarily drops when the setting of the engine lower limit rotational speed is canceled. That is, when the setting of the engine lower limit rotational speed is cancelled, there is a possibility that the passenger feels uncomfortable due to the lack of driving force. Such a problem is not yet known.

  The present invention has been made against the background of the above circumstances. The object of the present invention is to form a part of the power transmission path between the engine and the drive wheels, and the differential state is set by the differential motor. An object of the present invention is to provide a control device for a vehicular drive device that can suppress a drive force loss that may occur when canceling the setting of the engine lower limit rotation speed in a vehicular drive device including a controlled differential mechanism.

  To achieve the above object, the gist of the present invention is that (a) a differential state is controlled by a differential motor that forms part of a power transmission path between an engine and the engine and drive wheels. In the vehicle drive device provided with the differential mechanism, a control device for the vehicle drive device that sets the engine lower limit rotation speed when a predetermined manual setting operation is performed by an occupant, and (b) the engine When the lower limit rotational speed setting is canceled and the engine rotational speed is decreased, a rotational speed slow change process is executed to gradually decrease the engine rotational speed from a predetermined engine rotational speed change gradient. .

  By doing so, the change in the engine speed is moderated when the setting of the engine lower limit rotational speed is cancelled, and accordingly, the change in the rotational speed of the differential motor is also moderated. That is, the inertia generated according to the rotational acceleration of the differential motor approaches zero as compared with the case where the rotational speed gradual change process is not executed, so that it is possible to suppress the driving force loss. And possibility that the passenger | crew will be given the uncomfortable feeling resulting from the driving force omission is reduced. The engine lower limit rotation speed is a lower limit value of the engine rotation speed. If the engine lower limit rotation speed is set, the engine rotation speed is maintained at the engine lower limit rotation speed or higher.

  Here, preferably, (a) a manual operation member operated by the occupant is provided in a steering device for steering the traveling direction of the vehicle, and (b) the engine lower limit rotation speed is set. When the manual operation member is operated, the engine lower limit rotation speed is changed every time the manual operation member is operated. (C) The manual setting operation is a state in which the occupant is in the travel state where the engine lower limit rotation speed is not set. It is operating a manual operation member. In this way, the occupant can perform the manual setting operation in the same manner as the operation for switching the engine lower limit rotational speed that has already been set. Manual setting operation can be performed. In addition, since the manual operation member is provided in the steering device, an occupant (driver) can easily perform setting and switching of the engine lower limit rotation speed while operating the vehicle.

  Preferably, (a) manual release control is executed to release the setting of the engine lower limit rotation speed when a predetermined manual release operation is performed by the occupant, while the manual release operation is not performed and Automatic release control is executed to release the setting of the engine lower limit rotational speed when a predetermined automatic release condition is satisfied; (b) the rotational speed slow change process is performed during the automatic release control; Compared with the release control, the engine speed is gradually reduced. Here, since the manual release operation by the occupant is accompanied at the time of the manual release control, the occupant recognizes that it is caused by his own operation even if the driving force dropout occurs, and does not feel uncomfortable. On the other hand, since the setting of the engine lower limit rotational speed is automatically released during the automatic release control, the occupant tends to feel uncomfortable if the driving force dropout occurs. Further, from the viewpoint of improving fuel efficiency, it is preferable to reduce the engine rotational speed by removing the restriction on the engine lower limit rotational speed as soon as it is not necessary to increase the engine rotational speed. Therefore, with the above-described configuration, the engine speed is reduced earlier during the manual release control than in the automatic release control, so that it is possible to improve the fuel efficiency of the vehicle while avoiding a sense of discomfort to the occupant. It is possible to plan. For example, the fuel efficiency is a travel distance per unit fuel consumption, and the improvement in fuel efficiency is an increase in the travel distance per unit fuel consumption, or the fuel consumption rate ( = Fuel consumption / drive wheel output) is reduced. Conversely, a reduction in fuel consumption means that the travel distance per unit fuel consumption is shortened, or the fuel consumption rate of the entire vehicle is increased.

  Preferably, the automatic release condition is that the manual operation member is not operated and a traveling state in which the accelerator opening is equal to or greater than a predetermined accelerator opening determination value continues for a predetermined determination time or longer. Is established. In this way, when it is estimated that the occupant has lost the intention to continue setting the engine lower limit rotation speed after performing the manual setting operation, the automatic release condition can be satisfied. Accordingly, the setting of the engine lower limit rotational speed can be automatically canceled.

  Preferably, the engine lower limit rotational speed is set to be equal to or higher than the engine rotational speed before the manual setting operation when the occupant performs the manual setting operation. In this way, the occupant can immediately increase the engine rotational speed by the manual setting operation compared to before the above operation, so that the acceleration response when the accelerator is depressed can be quickly improved.

1 is a skeleton diagram for explaining a vehicle drive device to which the present invention is applied. It is the figure which illustrated the signal input into the electronic controller for controlling the vehicle drive device of FIG. 1, and the signal output from the electronic controller. FIG. 2 is a diagram illustrating an example of a shift operation device as a switching device (operation device) that switches a plurality of types of shift positions by an artificial operation in the vehicle drive device of FIG. 1. It is a figure which shows the steering device for a passenger | crew (driver | operator) to steer the advancing direction of a vehicle, (a) is a front view of the steering device, (b) is a side view of the steering device. It is a functional block diagram explaining the principal part of the control function with which the electronic control apparatus of FIG. 2 was equipped. It is the figure which showed an example of the reference | standard operation curve of the engine used in the engine control which the electronic controller of FIG. 2 performs. FIG. 3 is an engine lower limit rotation speed map showing a relationship between an engine lower limit rotation speed and a vehicle speed set by the electronic control unit of FIG. 2 in a manual shift mode for each virtual shift stage. The electronic control unit shown in FIG. 2 determines the engine braking force to be generated when the accelerator is turned off in the manual shift mode. The engine braking force is determined in advance with the driving force that is opposite to the engine braking force as the vertical axis and the vehicle speed as the horizontal axis. It is an engine brake force map which shows the set relationship. FIG. 6 is a collinear diagram for explaining a differential state of the first planetary gear device 20 when the setting of the engine lower limit rotational speed NLe is canceled in the vehicle drive device of FIG. 1. In the vehicle drive device of FIG. 1, as an example, when the setting of the engine lower limit rotation speed is canceled, the engine rotation speed is decreased from the engine lower limit rotation speed to the target engine rotation speed in the automatic shift mode. It is a time chart for demonstrating the rotational speed slow change process performed at the time of cancellation | release control. 2 is a flowchart for explaining a main part of the control operation of the electronic control device of FIG. 2, that is, a control operation in which the engine lower limit rotational speed is set or the setting is canceled when the shift position of the power transmission device is the D position. It is.

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

  FIG. 1 is a skeleton diagram for explaining a vehicle drive device 8 to which the present invention is applied. In FIG. 1, a vehicle drive device 8 includes an engine 14 that is an internal combustion engine such as a gasoline engine or a diesel engine, and a vehicle power transmission device 10 (hereinafter referred to as “drive power transmission device 10”) that transmits a drive force from the engine 14 to drive wheels 40. "Power transmission device 10"). The power transmission device 10 outputs the output of the engine 14 in turn from the engine 14 side in a transaxle (T / A) case 12 (hereinafter referred to as “case 12”) as a non-rotating member attached to the vehicle body. A damper 16 that is operatively connected to a shaft (for example, a crankshaft) and absorbs pulsation due to torque fluctuations from the engine 14, an input shaft 18 that is rotated by the engine 14 via the damper 16, a first electric motor M1, A first planetary gear device 20 that functions as a power distribution mechanism, a second planetary gear device 22 that functions as a speed reducer, and a second electric motor M2 that is connected to drive wheels 40 (see FIG. 5) so as to be able to transmit power. Yes.

  The power transmission device 10 is placed in front of a front wheel drive, that is, an FF (front engine / front drive) type vehicle 6 and is preferably used for driving the drive wheels 40. In the power transmission device 10, the power of the engine 14 includes an output gear 24 as an output rotation member of the power transmission device 10 constituting one of the counter gear pairs 32, a counter gear pair 32, a final gear pair 34, a differential gear device (final gear device). It is transmitted to the pair of drive wheels 40 through the reduction gear 36 and the pair of axles 38 in order (see FIG. 5). As described above, in this embodiment, the input shaft 18 and the engine 14 are operatively connected via the damper 16, and the output shaft of the engine 14 is an output rotating member of the engine 14. The input shaft 18 also corresponds to the output rotating member of the engine 14.

  Both ends of the input shaft 18 are rotatably supported by ball bearings 26 and 28, and one end of the input shaft 18 is connected to the engine 14 via the damper 16 to be driven to rotate by the engine 14. Further, an oil pump 30 as a lubricating oil supply device is connected to the other end, and the oil pump 30 is driven to rotate by rotating the input shaft 18, so that each part of the power transmission device 10, for example, the first planet. Lubricating oil is supplied to the gear device 20, the second planetary gear device 22, the ball bearings 26, 28, and the like.

  The first planetary gear device 20 is a differential mechanism connected between the engine 14 and the drive wheel 40. Specifically, the first planetary gear device 20 is a single pinion type planetary gear device, and includes a first pinion gear P1 and a first carrier CA1 as a first rotation element that supports the first pinion gear P1 so as to be capable of rotating and revolving. A first sun gear S1 as a second rotating element and a first ring gear R1 as a third rotating element that meshes with the first sun gear S1 via a first pinion gear P1 are provided as rotating elements (elements). The first planetary gear device 20 corresponds to the differential mechanism of the present invention.

  The first planetary gear device 20 is a mechanical power distribution mechanism that mechanically distributes the output of the engine 14 transmitted to the input shaft 18, and outputs the output of the engine 14 to the first electric motor M <b> 1 and the output gear 24. To distribute. That is, in the first planetary gear device 20, the first carrier CA1 is connected to the input shaft 18, that is, the engine 14, the first sun gear S1 is connected to the first electric motor M1, and the first ring gear R1 is connected to the output gear 24. Has been. As a result, the first sun gear S1, the first carrier CA1, and the first ring gear R1 can rotate relative to each other, so that the output of the engine 14 is distributed to the first electric motor M1 and the output gear 24, and The first electric motor M1 is generated by the output of the engine 14 distributed to the first electric motor M1, and the generated electric energy is stored or the second electric motor M2 is rotationally driven by the electric energy. For example, a continuously variable transmission state (electrical CVT state) is set, and the differential state of the first planetary gear device 20 is controlled by the first electric motor M1, so that the output gear 24 is controlled regardless of the predetermined rotation of the engine 14. It functions as an electric continuously variable transmission whose rotation is continuously changed.

  The second planetary gear unit 22 is a single pinion type planetary gear unit. The second planetary gear unit 22 includes a second sun gear S2, a second pinion gear P2, a second carrier CA2 that supports the second pinion gear P2 so as to rotate and revolve, and a second sun gear S2 via the second pinion gear P2. The meshing second ring gear R2 is provided as a rotating element. The ring gear R1 of the first planetary gear device 20 and the ring gear R2 of the second planetary gear device 22 are an integrated compound gear, and an output gear 24 is provided on the outer periphery thereof.

  In the second planetary gear device 22, the second carrier CA2 is coupled to the case 12 that is a non-rotating member to prevent rotation, the second sun gear S2 is coupled to the second electric motor M2, and the second ring gear R2 Is connected to the output gear 24. That is, the second electric motor M2 is connected to the output gear 24 and the ring gear R1 of the first planetary gear device 20 via the second planetary gear device 22. Thus, for example, when the vehicle starts, the second electric motor M2 is rotationally driven, whereby the second sun gear S2 is rotated, and the second planetary gear device 22 decelerates and transmits the rotation to the output gear 24.

  The first electric motor M1 and the second electric motor M2 of this embodiment are both so-called motor generators having a power generation function. The first electric motor M1 is a differential for controlling the operating state of the first planetary gear device 20. Since it functions as an electric motor, it has at least a generator (power generation) function for generating a reaction force. The second electric motor M2 functions as a traveling electric motor and has at least a motor (electric motor) function for outputting the driving force of the vehicle 6. Further, the first electric motor M1 and the second electric motor M2 are configured to be able to exchange power with each other.

  FIG. 2 illustrates a signal input to the electronic control device 100 that is a control device for controlling the vehicle drive device 8 of the present embodiment and a signal output from the electronic control device 100. The electronic control device 100 includes a so-called microcomputer including a CPU, a ROM, a RAM, an input / output interface, and the like, and performs signal processing according to a program stored in the ROM in advance while using a temporary storage function of the RAM. Is performed to execute vehicle control such as hybrid drive control for the engine 14, the first and second electric motors M1 and M2.

The electronic control unit 100 includes a signal representing the engine water temperature TEMP _W , a signal from the engine rotation speed sensor representing the engine rotation speed Ne, which is the rotation speed of the engine 14, and an output from each sensor and switch as shown in FIG. A signal from a vehicle speed sensor representing a vehicle speed V corresponding to a rotational speed N _OUT of the gear 24 (hereinafter referred to as “output rotational speed N _OUT ”), a signal representing a foot brake operation, and an accelerator pedal corresponding to a driver's output request amount A signal indicating the accelerator opening Acc, which is the operation amount of the vehicle, a signal indicating the throttle valve opening θ _TH of the electronic throttle valve 62, a signal indicating the longitudinal acceleration G of the vehicle 6, and each wheel (ie, the driven wheel 40 is added) signals representing the wheel speed of each wheel) was, the rotational speed N _M1 of the first electric motor M1 _{(hereinafter,} a signal representative of the) as "first electric motor speed N _M1", the second conductive Rotational speed N _M2 of the machine M2 _{(hereinafter,} referred to as "second electric motor rotation speed N _M2") signal representing a signal representing the remaining charge (state of charge) SOC of the battery 56, the operating position of the shift lever 44 (operating position ) shift lever position signal corresponding to the operation position P _OPE from lever position sensor 48 is a position sensor for detecting the P _OPE, the shift position P _SH of the parking position of being operated by the driver power transmission device 10 ( P switch signal indicating switch operation at the P switch 46 for switching from a non-P position other than (P position) to the P position, a signal indicating that the upshift paddle 76U from the upshift detection switch 80 has been operated, and downshift detection A signal indicating that the downshift paddle 76D from the switch 82 has been operated is displayed. , Each supplied. In the following description, the upshift paddle 76U and the downshift paddle 76D are simply referred to as the paddle 76 unless otherwise distinguished.

Further, a control signal from the electronic control device 100 to an engine output control device 58 (see FIG. 5) for controlling the engine output, for example, a throttle valve opening θ _TH of an electronic throttle valve 62 provided in the intake pipe 60 of the engine 14. A command for a drive signal to the throttle actuator 64 for operating the engine, a fuel supply amount signal for controlling the fuel supply amount to the intake pipe 60 or the cylinder of the engine 14 by the fuel injection device 66, and an ignition timing of the engine 14 by the ignition device 68 are commanded. The vehicle information display device 52 installed at a position where the driver in the vehicle can easily visually recognize the ignition signal, the command signal for instructing the operation of each of the motors M1 and M2, and the vehicle information related to the vehicle running is currently displayed on the vehicle information display device 52. speed display control command signal for displaying the vehicle speed V, and displays the switching state of the shift position P _SH in the vehicle information display device 52 Shift position display control command signals because, during operation of the P-lock (parking lock state, the P lock state) P position indicator lamp as lock indicator lamp for or shift position P _SH is evidenced by lighting it is in P position A parking lock display control command signal and the like for displaying the P lock state by operating 50 is output. The P position indicator lamp 50 is a display lamp that is operated without being interlocked with the operation (lighting / extinguishing) of the vehicle information display device 52. For example, the P position indicator lamp 50 is provided in the P switch 46.

FIG. 3 is a diagram illustrating an example of a shift operation device 42 as a switching device (operation device) for switching a plurality of types of shift positions _PSH by an artificial operation in the power transmission device 10. The shift operation device 42 is disposed, for example, in the vicinity of the driver's seat, and automatically returns to the original position (initial position) when the momentary type operation element operated to the plurality of operation positions _POPE , that is, the operation force is released. A shift lever 44 as an automatic return type operator and a lever operation position sensor 48 (see FIG. 2) are provided. The shift operating device 42 of this embodiment, the vicinity of the shift lever 44 a P switch 46 as momentary operation element for the parking lock a shift position P _SH of the power transmission device 10 as a parking position (P position) Is provided as a separate switch.

As shown in FIG. 3, the shift lever 44 has three operation positions P _OPE arranged in the front-rear direction or the up-down direction, that is, the vertical direction of the vehicle 6, R operation position (R operation position), N operation position (N operation position). ), The D operation position (D operation position), and the M operation position (M operation position) and S operation position (S operation position) arranged in parallel therewith, respectively. 42 outputs a shift lever position signal corresponding to the operation position P _OPE to the electronic control unit 100. The shift lever 44 can be operated in the vertical direction among the R operation position, the N operation position, and the D operation position, and can be operated in the vertical direction between the M operation position and the S operation position. Further, the vehicle can be operated in the lateral direction of the vehicle perpendicular to the longitudinal direction between the N operation position and the M operation position.

The P switch 46 is, for example, a momentary push button switch, and outputs a P switch signal to the electronic control device 100 every time a push operation is performed by a user such as a driver. For example, when the P switch 46 is pressed when the shift position P _SH of the power transmission device 10 is in the non-P position, the electronic control device 100 is satisfied if a predetermined condition such as the vehicle 6 is substantially stopped is satisfied. As a result, the shift position _PSH is set to the P position. The P position is a parking position in which the power transmission path in the power transmission device 10 is interrupted, and parking lock is performed to mechanically block the rotation of the drive wheels 40 by a well-known parking lock device. The P switch 46 has a built-in P position indicator lamp 50. The P position indicator lamp 50 is turned on when the shift position _PSH is set to the P position.

The M operation position of the shift operation device 42 is the initial position (home position) of the shift lever 44, even if the shift operation is performed to an operation position P _OPE (R, N, D, S operation position) other than the M operation position. When the driver releases the shift lever 44, that is, when there is no external force acting on the shift lever 44, the shift lever 44 returns to the M operation position by a mechanical mechanism such as a spring. When the shift operating device 42 is shift-operated to the operating position P _OPE is corresponding to the operation position P _OPE after the shifting operation based on the shift lever position signal corresponding to the operating position P _OPE by the electronic control device 100 with is switched to the shift position P _SH, the state of the shift position P _SH of the current shift position P _SH or power transmission device 10 is displayed on the vehicle information display device 52.

The shift position P _SH will be described. The R position selected by the shift lever 44 being shifted to the R operation position is a reverse travel position in which a driving force for moving the vehicle backward is transmitted to the drive wheels 40. The neutral position (N position) selected by shifting the shift lever 44 to the N operation position is a neutral position for setting the neutral state in which the power transmission path in the power transmission device 10 is interrupted. . The D position selected by shifting the shift lever 44 to the D operation position is a forward travel position in which a driving force for moving the vehicle 6 forward is transmitted to the drive wheels 40. For example, the electronic control unit 100 determines a predetermined operation position P _OPE for releasing the parking lock when the shift position P _SH is the P position (specifically, the R operation position, the N operation position, or the D operation position). If a predetermined condition such as the brake-on state B _ON is satisfied, the parking lock device is activated to release the parking lock, and the post-shift operation is performed. in the operating position P _OPE switched to the shift position P _SH corresponding.

Further, the S position selected by the shift lever 44 being shifted to the S operation position is such that the engine wheel effect is exerted by the regenerative braking that causes the second electric motor M2 to generate regenerative torque in the D position. This is a decelerating forward travel position (engine brake range) that decelerates the rotation of the engine. Therefore, the electronic control unit 100 invalidates the shift operation even if the shift lever 44 is shifted to the S operation position when the current shift position _PSH is a shift position other than the D position, and is in the D position. Only the shift operation to the S operation position is valid. For example, even if the driver performs a shift operation to the S operation position at the P position, the shift position _PSH is continued as the P position.

In the shift operation device 42 of the present embodiment, when the external force acting on the shift lever 44 disappears, the shift operation device 42 returns to the M operation position, so that the shift position P _SH being selected can be recognized only by visually recognizing the operation position P _OPE of the shift lever 44. I can't do it. Therefore, the vehicle information display device 52 is provided at a position that is easy to see for the driver, and is displayed on the vehicle information display device 52 (see FIG. 2) including the case where the currently selected shift position _PSH is the P position. It has become.

When the selected shift position _PSH is the D position, basically, the traveling mode (shift mode) of the vehicle 6 is automatically different from that of the first planetary gear device 20 according to the traveling state of the vehicle 6. This is an automatic transmission mode in which the operating state and the engine rotational speed Ne are controlled, but the engine lower limit rotational speed NLe, which is the lower limit value of the engine rotational speed Ne, is changed in stages according to the manual operation of the passenger (sequential Mode). In this manual shift mode, the virtual transmission of the power transmission device 10 is realized by changing the engine rotation speed Ne by limiting the engine lower limit rotation speed NLe. In the virtual manual shift of the power transmission device 10, increasing the engine lower limit rotation speed NLe corresponds to downshifting, and decreasing the engine lower limit rotation speed NLe corresponds to upshifting. When switched to the manual shift mode, for example, the manual shift mode and the current virtual shift stage are displayed at positions that are easy for the occupant (driver) to see.

  FIG. 4 is a diagram showing a steering device 70 for an occupant (driver) to steer the traveling direction of the vehicle 6, FIG. 4 (a) is a front view of the steering device 70, and FIG. 4 (b). 3 is a side view of the steering device 70. FIG. The steering device 70 is provided in the vehicle 6 and includes a steering column 72 fixed to the vehicle body so as not to rotate, a steering wheel 74 disposed on the occupant side of the steering column 72 and rotatable relative to the steering column 72. It has. The occupant can steer the traveling direction of the vehicle 6 by rotating the steering wheel 74.

  As shown in FIG. 4, a pair of paddle switches 76U and a downshift paddle 76D, which are a pair of paddle switches operated by the occupant, are provided in the steering column 72 in the vicinity of the steering wheel 74. The upshift paddle 76U is a manual operation member that is operated by the occupant to lower the engine lower limit rotational speed NLe for each operation when the manual shift mode is selected, and the downshift paddle 76D is selected for the manual shift mode. At this time, it is a manually operated member that is operated by the occupant to raise the engine lower limit rotational speed NLe for each operation. Each of the upshift paddle 76U and the downshift paddle 76D is operated by pulling the front end portion toward the front side (driver side), so that the front end portion rotates about the base end portion as a fulcrum. When the force is released, it is configured to automatically return to the original position by a spring or the like. Note that the operation toward the front side of the upshift paddle 76U is detected by the upshift detection switch 80, and the operation toward the front side of the downshift paddle 76D is detected by the downshift detection switch 82.

  FIG. 5 is a functional block diagram for explaining a main part of the control function provided in the electronic control device 100. As shown in FIG. 5, the electronic control unit 100 includes a hybrid control unit 102 as a hybrid control unit, a manual operation detection unit 104 as a manual operation detection unit, a transmission mode switching unit 106 as a transmission mode switching unit, A shift mode determination unit 110 as a shift mode determination unit and an automatic release determination unit 112 as an automatic release determination unit are provided. The hybrid control unit 102 includes a manual shift mode control unit 108 as a manual shift mode control unit.

  In FIG. 5, the hybrid control means 102 operates the engine 14 in an efficient operating range, while optimizing the reaction force due to the distribution of the driving force between the engine 14 and the second electric motor M2 and the power generation of the first electric motor M1. Thus, the speed ratio γ0 as an electric continuously variable transmission of the power transmission device 10 is controlled. For example, at the traveling vehicle speed V at that time, the target (request) output of the vehicle is calculated from the accelerator opening Acc and the vehicle speed V as the driver's required output amount, and the total required from the target output and the required charging value of the vehicle. A target output is calculated, and a target engine output Pe * is calculated in consideration of transmission loss, auxiliary load, assist torque of the second motor M2, etc. so that the total target output is obtained. The engine 14 is controlled so that the obtained engine rotational speed Ne and the output torque Te (engine torque Te) of the engine 14 are obtained, and the power generation amount of the first electric motor M1 is controlled. At the same time, the speed ratio γ0 of the power transmission device 10 is changed within a changeable range so that the engine rotational speed Ne and the engine torque Te at which the target engine output Pe *, which is the target value of the engine output Pe, is obtained. Control steplessly within. The hybrid control means 102 controls the engine 14 so that the engine rotational speed Ne and the engine torque Te at which the target engine output Pe * is obtained as described above will be described in detail later.

  When the hybrid control means 102 controls the power generation amount of the first motor M1, the electric energy generated by the first motor M1 is supplied to the power storage device 56 and the second motor M2 through the inverter 54. Is mechanically transmitted to the output gear 24, but a part of the power of the engine 14 is consumed for power generation of the first electric motor M <b> 1, where it is converted into electric energy, and the electric energy is converted through the inverter 54. The electric power is supplied to the second electric motor M2, and the second electric motor M2 is driven and transmitted from the second electric motor M2 to the output gear 24. An electric path from conversion of part of the motive power of the engine 14 into electric energy and conversion of the electric energy into mechanical energy by a device related to the generation of the electric energy until it is consumed by the second electric motor M2 Composed. The power storage device 56 is, for example, a battery (secondary battery) such as a lead storage battery or a capacitor, and supplies power to the first electric motor M1 and the second electric motor M2 and supplies electric power from each of the electric motors M1 and M2. There is an electrical energy source that can be supplied, that is, an electrical energy source that can transfer power to each of the first electric motor M1 and the second electric motor M2.

Further, the hybrid control means 102 controls the first motor rotation speed N _M1 and keeps the engine rotation speed Ne substantially constant by the electric CVT function of the power transmission device 10 regardless of whether the vehicle is stopped or traveling. The rotation is controlled at an arbitrary rotation speed. That is, the hybrid control means 102 drives the first electric motor M1 operatively connected to the input shaft 18 (that is, the output shaft of the engine 14) via the first planetary gear device 20 so that power can be transmitted to the input shaft 18. By making it function as a device, the engine 14 is driven to rotate by the first electric motor M1. For example, when the engine speed Ne is increased while the vehicle is traveling, the hybrid control means 102 maintains the output rotation speed N _OUT restricted by the vehicle speed V (drive wheel 40) substantially constant, and the first motor rotation speed N. _M1 is raised.

Further, the hybrid control means 102 controls the fuel injection amount and the injection timing by the fuel injection device 66 for the fuel injection control in addition to controlling the opening and closing of the electronic throttle valve 62 by the throttle actuator 64 for the throttle control. A command for controlling the ignition timing of the ignition device 68 such as an igniter for control is output to the engine output control device 58 alone or in combination, and the output control of the engine 14 is executed so as to generate the necessary engine output. . For example, the hybrid control means 102, drives the throttle actuator 60 based on the accelerator opening Acc, the accelerator opening Acc is to perform the throttle control to increase the throttle valve opening theta _TH enough to increase. Further, the engine output control device 58 controls the opening and closing of the electronic throttle valve 62 by the throttle actuator 64 for throttle control according to the command from the hybrid control means 102, and the fuel injection by the fuel injection device 66 for fuel injection control. The engine torque control is executed by controlling the ignition timing by an ignition device 68 such as an igniter for controlling the ignition timing.

Further, the hybrid control means 102 drives the second electric motor M2 with the electric power from the power storage device 56 in a state where the operation of the engine 14 is stopped, and uses only the second electric motor M2 as a driving force source for the vehicle 6 (see FIG. EV traveling) can be executed. For example, the EV traveling by the hybrid control means 102 is relatively low in the output torque T _OUT region, that is, the low engine torque Te region or the vehicle speed V, which is generally considered to be poor in engine efficiency as compared with the high torque region. It is executed in a low vehicle speed range, that is, a low load range.

  In this EV traveling, the hybrid control means 102 idles, for example, by putting the first electric motor M1 in a no-load state in order to suppress dragging of the engine 14 that is stopped and improve fuel efficiency. The engine speed Ne is maintained at zero or substantially zero as required by the electric CVT function (differential action) of the transmission device 10. That is, the hybrid control means 102 does not simply stop the operation of the engine 14 during EV traveling, but also stops the rotation of the engine 14.

Further, the hybrid control means 102 functionally includes an engine start control means for starting the engine 14 while the vehicle is stopped or during EV traveling. For example, the hybrid control means 102 can complete the engine rotation speed Ne by energizing the first electric motor _M1 to increase the first electric motor rotation speed NM1, that is, by causing the first electric motor M1 to function as a starter. The fuel injection device 66 supplies (injects) fuel at an engine rotation speed Ne that can be autonomously rotated at a predetermined rotation speed Ne ′ or higher, for example, at an engine rotation speed Ne that is autonomous rotation or higher at a predetermined rotation speed Ne ′ or higher. And the engine 14 is started.

  Further, the hybrid control means 102 uses the electric energy from the first electric motor M1 and / or the electric energy from the power storage device 56 by the electric path described above during the engine running using the engine 14 as a driving force source. , And driving the second electric motor M2 to apply torque to the drive wheels 40, so-called torque assist for assisting the power of the engine 14 is possible.

  Further, the hybrid control means 102 makes the first motor M1 in a no-load state and freely rotates, that is, idles, so that the power transmission device 10 cannot transmit torque, that is, the power transmission path in the power transmission device 10 is interrupted. It is possible to set the second electric motor M2 in a no-load state so that no output from the power transmission device 10 is generated. That is, the hybrid control means 102 can place the power transmission device 10 in the neutral state by setting the electric motors M1 and M2 to a no-load state.

  In addition, the hybrid control means 102 rotates the second electric motor M2 by the kinetic energy of the vehicle, that is, the reverse driving force transmitted from the driving wheel 40 to the second electric motor M2 side when the vehicle is decelerated or braked with the accelerator off. It functions as a regenerative brake control means for performing so-called regenerative braking in which the electric power generated by the second motor M2 is driven and charged to the power storage device 56 via the inverter 54.

As described above, the hybrid control unit 102 controls the engine 14 so that the engine rotational speed Ne and the engine torque Te at which the target engine output Pe * is obtained. The engine control will be described in detail below. In the present embodiment, the hybrid control means 102 stores in advance a reference operation curve _LEF that serves as a reference for engine operation during traveling. FIG. 6 is a diagram showing an example of the reference operation curve _LEF of the engine 14. For example, the reference operation curve _LEF is an optimum fuel consumption rate curve that is experimentally preset so as to achieve both driving performance and fuel consumption performance. The hybrid control unit 102 functions as an engine drive control unit, that is, an engine drive control unit in engine control, so that the target engine output is set so that the operating point P _EG (engine operating point P _EG ) of the engine 14 follows the reference operating curve L _EF. Based on Pe *, the target engine speed Ne * and the target engine torque Te * are determined, and the engine speed Ne and the engine torque Te are set to the determined target engine speed Ne * and the target engine torque Te *, respectively. The engine 14 is operated so as to match. For example, in determining the hybrid control means 102 from the reference operating curve L _EF and the target engine rotational speed Ne * and the target engine torque Te * is equal power curve and the reference operation had been chosen point indicating the target engine output Pe * The intersection with the curve _LEF indicates the target engine speed Ne * and the target engine torque Te *.

In the present embodiment, the traveling mode when the shift position _PSH of the power transmission device 10 is the D position includes an automatic transmission mode and a manual transmission mode, and the hybrid control means 102 is in any traveling mode as described above. While operating the engine 14 along the reference operation curve L _EF, while the engine rotation speed lower limit NLe in the manual shift mode is set, in the automatic shift mode engine rotation speed lower limit NLe is released. Next, engine control in the manual shift mode will be described.

  The manual operation detecting means 104 detects that the upshift paddle 76U and the downshift paddle 76D are operated from the detection signals of the upshift detection switch 80 and the downshift detection switch 82, respectively, and the upshift paddle 76U and the downshift paddle 76D. It is determined whether or not each of these has been operated. The operation of the paddle 76 includes a long press operation in which the paddle 76 is pressed long and an operation not corresponding to the long press operation, that is, an instantaneous operation in which the paddle 76 is instantaneously operated. Therefore, the manual operation detection unit 104 stores in advance a long press determination time that is experimentally set in advance so that the long press operation can be determined as soon as possible in accordance with the intention of the operator. Then, when the paddle 76 is operated, the manual operation detecting means 104 determines that the paddle 76 is the long press operation when the operation of the paddle 76 continues for the long press determination time. If the operation 76 is released before the long press determination time has elapsed, it is determined that the operation is the instantaneous operation.

Shift mode switching means 106, when the shift position P _SH of the power transmission device 10 is the D position, selectively switching the travel mode of the vehicle 6 in said manual shift mode and the automatic shift mode. For example, the shift mode switching means 106 sets the travel mode to the manual shift mode when a predetermined manual shift mode selection operation for switching the automatic shift mode to the manual shift mode is performed by the occupant in the D position automatic shift mode. Switch to. Although the manual shift mode selection operation is not particularly limited, the manual shift mode selection operation of the present embodiment is that the upshift paddle 76U or the downshift paddle 76D is operated in the automatic shift mode of the D position. The switching unit 106 determines whether or not there is a manual shift mode selection operation based on the determination of the manual operation detection unit 104. The manual shift mode selection operation corresponds to the manual setting operation of the present invention.

  On the other hand, the shift mode switching means 106 automatically switches the travel mode when a predetermined automatic shift mode selection operation for switching the manual shift mode to the automatic shift mode is performed by the occupant in the manual shift mode of the D position. Switch to shift mode. Although there is no particular limitation on the automatic transmission mode selection operation, the automatic transmission mode selection operation of the present embodiment is performed when the upshift paddle 76U is pressed and held in the D-position manual transmission mode and the shift lever 44 is operated in the D operation position. The shift mode switching means 106 determines whether or not the upshift paddle 76U has been pressed for a long time based on the determination of the manual operation detection means 104. In other words, the automatic transmission mode selection operation is a manual transmission mode release operation, and corresponds to the manual release operation of the present invention.

Furthermore, the shift mode switching means 106 may automatically switch the travel mode to the automatic shift mode even if the automatic shift mode selection operation is not performed in the manual shift mode of the D position. Specifically, the shift mode switching means 106 switches the travel mode to the automatic shift mode when a predetermined manual shift mode release condition is satisfied. The manual shift mode release condition is not particularly limited as long as it is determined to be satisfied when it is estimated that the occupant has lost the intention to continue the manual shift mode. The release condition is that the driving state in which neither the upshift paddle 76U nor the downshift paddle 76D is operated and the accelerator opening degree Acc is equal to or greater than a predetermined accelerator opening degree determination value LAcc is a predetermined determination time TIME _RL. It is established when the above is continued. For example, the accelerator opening determination value LAcc is experimentally determined so that it can be determined that the occupant does not need engine braking (generation of reverse driving force), and the determination time TIME _RL is manually determined by the occupant. It is experimentally determined so that it can be estimated that the intention to continue the shift mode has been lost. The manual shift mode cancel condition corresponds to the automatic cancel condition of the present invention.

The hybrid control means 102 operates the engine 14 in accordance with the travel mode of the vehicle 6 set by the shift mode switching means 106. Specifically, the hybrid control means 102 operates the engine 14 along the reference operation curve LE _F as described above, but the manual shift mode control means 108 provided in the hybrid control means 102 includes the shift mode switching means 106. wherein the travel mode when switching from the automatic shift mode to the manual shift mode, the sets the engine rotation speed lower limit NLe, in preference to the reference operation curve L _EF, differential state of the first planetary gear set 20 and by controlling the throttle valve opening theta _TH to keep the engine rotational speed Ne to the above engine lower limit speed NLe. On the other hand, the manual shift mode control means 108 cancels the setting of the engine lower limit rotational speed NLe when the shift mode switching means 106 switches the travel mode from the manual shift mode to the automatic shift mode. That is, the manual transmission mode is a traveling state in which the engine lower limit rotational speed NLe is set, and the automatic transmission mode is a traveling state in which the engine lower limit rotational speed NLe is not set.

  Further, when the shift mode switching means 106 switches the travel mode from the automatic shift mode to the manual shift mode, the manual shift mode control means 108 sets the engine lower limit rotational speed NLe as described above. The engine rotation speed Ne is sequentially detected, and the engine lower limit rotation speed NLe is set to be equal to or higher than the engine rotation speed Ne before switching to the manual shift mode, that is, before the manual shift mode selection operation. Further, during the manual shift mode, every time the downshift paddle 76D is instantaneously operated, the virtual shift stage of the power transmission device 10 is changed to the low vehicle speed side, while the upshift paddle 76U is The virtual shift speed is changed to a higher vehicle speed each time the instantaneous operation is performed, but the manual shift mode control means 108 performs two manual shifts in accordance with the change of the virtual shift speed, that is, the virtual shift. Time control is performed. The first manual shift control is to change the engine lower limit rotational speed NLe stepwise each time the paddle 76 is operated. For example, in order to perform the first manual shift control, as shown in FIG. 7, the engine lower limit rotational speed NLe increases as the virtual shift speed in the manual shift mode is lower or the vehicle speed V is higher. A relationship to be set, that is, an engine lower limit rotation speed map is set in advance. Then, in the first manual shift control, the manual shift mode control means 108 sets the engine lower limit rotation speed NLe based on the vehicle speed V from the engine lower limit rotation speed map of FIG. In FIG. 7, S1 to S5 respectively indicate the above-described virtual shift speeds. For example, S1 is the first speed of the virtual shift speed (the shift speed on the lowest vehicle speed side), and S5 is the fifth speed (highest speed). (Speed stage on the vehicle speed side). For example, in FIG. 7, when the vehicle speed V is V1, the engine lower limit rotational speed NLe is set to NLe3 at the virtual third speed and is set to NLe2 (> NLe3) at the virtual second speed. In the first speed, it is set to NLe1 (> NLe2). That is, the manual shift mode control means 108 increases the engine lower limit rotational speed NLe stepwise every time the downshift paddle 76D is operated instantaneously, while the engine lower limit rotation is performed every time the upshift paddle 76U is operated instantaneously. Decrease speed NLe step by step. The manual shift mode control means 108 sets the engine lower limit rotation speed NLe to be equal to or higher than the engine rotation speed Ne before switching when switching from the automatic shift mode to the manual shift mode as described above. In this case, on the basis of the vehicle speed V from the engine lower limit rotational speed map of FIG. 7, the speed stage on the highest vehicle speed side among the virtual speed stages in which the engine lower limit rotational speed NLe is equal to or higher than the engine rotational speed Ne before switching. Is selected.

  The second manual shift control of the two manual shift controls is a direction in which the driving wheel 40 is braked in a no-load operation state of the engine 14, that is, an accelerator-off travel state in which the accelerator opening degree Acc is zero. In other words, the reverse driving force, that is, the engine braking force to be generated is changed stepwise every time the paddle 76 is operated. For example, in the second manual shift control, the manual shift mode control means 108 controls the differential state of the first planetary gear device 20 and regenerates the second electric motor M2 in the accelerator-off running state. The engine braking force is generated according to FIG. FIG. 8 shows an engine brake force map which is a preset relationship between the engine brake force and the vehicle speed V. The horizontal axis in FIG. 8 represents the vehicle speed V, and the vertical axis represents the engine brake force. The driving force having positive and negative signs is shown, and S1 to S5 in FIG. 8 have the same meaning as in FIG. 7, and D indicates the automatic transmission mode. In the engine brake force map, the engine brake force is set to be larger as the virtual gear position in the manual shift mode is on the lower vehicle speed side or the vehicle speed V is higher. Therefore, as can be seen from FIG. 8, if the vehicle speed V does not change, for example, the manual shift mode control means 108 increases the engine braking force step by step every time the downshift paddle 76D is operated instantaneously while the accelerator is off. On the other hand, every time the upshift paddle 76U is instantaneously operated, the engine braking force is gradually reduced.

  As described above, the manual shift mode control means 108 cancels the setting of the engine lower limit rotational speed NLe when the shift mode switching means 106 switches the travel mode from the manual shift mode to the automatic shift mode. Since the engine rotation speed Ne is limited so as not to decrease below the engine lower limit rotation speed NLe during the manual shift mode, the engine rotation speed Ne may decrease with the cancellation of the setting of the engine lower limit rotation speed NLe. For example, as can be seen from FIG. 7, the lower the vehicle speed side, the lower the engine speed Ne that has been selected before the manual shift mode is released, the lower the engine speed Ne associated with the cancellation of the engine lower limit engine speed NLe. Easy to do. A change in driving force when the engine rotational speed Ne decreases will be described with reference to FIG.

FIG. 9 is a collinear diagram for explaining the differential state of the first planetary gear device 20 when the setting of the engine lower limit rotational speed NLe is cancelled. The vertical lines Y1, Y2, and Y3 in FIG. 9 are integrated with the first sun gear S1 that rotates integrally with the first electric motor M1, the first carrier CA1 that rotates together with the engine 14, and the output gear 24 in this order from the left side. The respective relative rotational speeds of the first ring gear R1 rotating in the direction are shown. As shown in FIG. 9, the engine torque Te is transmitted to the output gear 24 by generating an output torque T _M1 (hereinafter, referred to as a first motor torque T _M1 ) of the first electric motor M1 that opposes the engine torque Te. The torque transmitted to the output gear 24 is referred to as a direct torque Tep. The direct torque Tep and the output torque T _M2 of the second electric motor _M2 (hereinafter referred to as the second electric motor torque T _M2 ) are combined and transmitted to the drive wheels 40 to generate a driving force. The direct torque Tep is calculated by the following formula (1). In the following formula (1), I _M1 is the moment of inertia of the first electric motor M1, ω _M1 is the angular velocity of the first electric motor M1, and dω _M1 / dt is the angular acceleration, that is, the rotational speed change of the first electric motor M1. , Ρ is the gear ratio of the first planetary gear unit 20, and the gear ratio ρ is expressed by the following formula (2), where the number of teeth of the first ring gear R1 is Z _R1 and the number of teeth of the first sun gear S1 is Z _S1. Calculated.
Tep = −1 / ρ × (T _M1 −I _M1 × dω _M1 / dt) (1)
ρ = Z _S1 / Z _R1 (2)

When the engine rotational speed Ne decreases as the engine lower limit rotational speed NLe is released, the rotational speed of the output gear 24 is constrained to the vehicle speed V as can be seen from FIG. The first motor rotation speed N _M1, that is, the angular speed ω _M1 also decreases. Then, as the change in the engine rotational speed Ne at that time becomes more rapid, the absolute value of dω _M1 / dt in the above equation (1) temporarily increases in the negative direction. Therefore, as can be seen from the above equation (1), The direct torque Tep temporarily falls with the change in the engine speed Ne. That is, since the driving force is based on the direct torque Tep, if the engine rotation speed Ne is suddenly reduced when the setting of the engine lower limit rotation speed NLe is canceled, a driving force drop occurs in which the driving force temporarily drops. Further, as described above, since the setting of the engine lower limit rotational speed NLe may be automatically canceled without the occupant performing the automatic transmission mode selection operation, the setting of the engine lower limit rotational speed NLe is thus performed. If it is automatically released and the driving force loss occurs, the passenger may feel uncomfortable with the driving force loss. Therefore, in this embodiment, a control function is provided that suppresses the occupant's uncomfortable feeling caused by the loss of driving force when the setting of the engine lower limit rotational speed NLe is cancelled. This will be described below.

Shift mode determining means 110, the shift position P _SH of the power transmission device 10 in a case where the D position, it is determined whether the running mode of the vehicle 6 is in the manual shift mode. Specifically, if the shift mode switching unit 106 selects the manual shift mode, it is determined that the travel mode is the manual shift mode, and if the shift mode switch unit 106 selects the automatic shift mode, the automatic shift mode is selected. Judge that there is.

  The automatic release determination unit 112 is configured to switch from the manual shift mode by the shift mode switching unit 106 to the automatic shift mode when the shift mode determination unit 110 switches to the determination to affirm that the travel mode is the manual shift mode. It is determined whether or not the shift to, that is, the release of the manual shift mode is automatic. Specifically, the release of the manual shift mode due to the establishment of the manual shift mode release condition is an automatic release of the manual shift mode. On the other hand, the release of the manual shift mode due to the operation of selecting the automatic shift mode is not the automatic release of the manual shift mode but the manual release.

  As described above, the manual shift mode control means 108 cancels the setting of the engine lower limit rotational speed NLe when the shift mode switching means 106 switches the travel mode from the manual shift mode to the automatic shift mode. Engine control is performed in consideration of the determination of the automatic release determination means 112. Specifically, the manual shift mode control means 108, when the automatic release determination means 112 determines that the release of the manual shift mode is automatic, is accompanied by the release of the setting of the engine lower limit rotational speed NLe. When the engine rotational speed Ne is decreased, a rotational speed slow change process (rotational speed slow change control) is performed in which the engine rotational speed Ne is gradually decreased below a predetermined engine rotational speed change gradient ΔNe. That is, when the setting of the engine lower limit rotational speed NLe is canceled and the engine rotational speed Ne is decreased, the above-described rotational speed slow change process is executed. On the other hand, the manual shift mode control means 108 performs the above-described rotational speed gradual change processing when the automatic release determination means 112 does not determine that the manual shift mode is automatically released, that is, in the case of manual release. However, in this embodiment, the engine rotational speed Ne is immediately reduced without executing the slow rotational speed change process.

  As described above, there are two methods for canceling the setting of the engine lower limit rotational speed NLe, and the manual shift mode control means 108 performs the manual shift mode canceling operation (automatic shift mode selection) when canceling the setting of the engine lower limit rotational speed NLe. When the operation is performed, the manual lowering control is performed to cancel the setting of the engine lower limit rotational speed NLe and immediately decrease the engine rotational speed Ne, while the manual shift mode canceling operation is not performed and the manual shift mode canceling condition is It can be said that automatic release control is executed to cancel the setting of the engine lower limit rotational speed NLe and execute the slow rotational speed change process when the above is established.

  The engine rotational speed change gradient ΔNe in the rotational speed slow change process is experimentally determined so that the engine rotational speed Ne can be reduced without causing the occupant to feel the loss of driving force. It is determined so that the engine rotational speed Ne can be gradually reduced as compared with the manual release control. The engine rotational speed change gradient ΔNe is determined by the amount of decrease per unit time of the engine rotational speed Ne. Further, the rotational speed slow change process can be described with reference to FIG.

FIG. 10 shows an example in which the engine speed Ne is decreased from the engine lower limit speed NLe to Ne1 *, which is the target engine speed Ne * in the automatic transmission mode, in accordance with the cancellation of the setting of the engine lower limit speed NLe. FIG. 6 is a time chart for explaining the rotational speed gradual change process executed during the automatic release control. The time point t1 in FIG. 10 is the time of automatic switching from the manual shift mode to the automatic speed change mode, that is, the automatic lowering of the engine lower limit rotational speed NLe, and the time point t2 is the rotational speed slow change process in the automatic release control. At the end of If the manual shift mode control means 108 executes the manual release control, the target engine speed Ne * is set to Ne1 * from the time point t1, so the manual speed change mode control means 108 keeps the engine lower limit rotation speed until the time point t1. The engine rotational speed Ne maintained at NLe is decreased toward the target engine rotational speed Ne1 * immediately after time t1, as indicated by a broken line in FIG. However, the manual shift mode control means 108 executes the slow speed change process from time t1 to time t2 during the automatic release control, and the target engine speed Ne * reaches Ne1 * at time t2. As indicated by the solid line, the engine rotational speed Ne slowly decreases from the engine lower limit rotational speed NLe toward the target engine rotational speed Ne1 * from the time point t1 to the time point t2, whereby the first electric motor in the equation (1) is obtained. The absolute value of the angular acceleration dω _M1 / dt of _M1 is suppressed from temporarily increasing. As can be seen by comparing the change in the engine speed Ne indicated by the solid line between the time t1 and the time t2 in FIG. 10 and the change in the engine speed Ne indicated by the broken line, the slow speed change process is performed as described above. Compared with the manual release control, the engine rotational speed Ne is gradually reduced.

Figure 11 is a main control operation of the electronic control device 100, i.e., the control operation of the shift position P _SH of the power transmission device 10 is an engine rotation speed lower limit NLe is set or the setting is canceled when a D position Is repeatedly executed with an extremely short cycle time of about several milliseconds to several tens of milliseconds, for example. For example, the flowchart of FIG. 11 is executed when the shift position _PSH is the D position.

  First, in step (hereinafter, “step” is omitted) SA1 corresponding to the shift mode determining means 110, it is determined whether or not the traveling mode of the vehicle 6 is the manual shift mode, that is, the sequential mode. If the shift mode switching means 106 selects the manual shift mode, the travel mode is determined to be the manual shift mode, and if the shift mode switching means 106 selects the automatic shift mode, it is determined to be the automatic shift mode. If the determination at SA1 is affirmative, that is, if the travel mode is the manual shift mode, the routine proceeds to SA2. On the other hand, if the determination at SA1 is negative, the operation goes to SA3.

  In SA2 corresponding to the manual shift mode control means 108, the engine lower limit rotational speed NLe is set. Further, the engine lower limit rotational speed NLe is increased stepwise every time the downshift paddle 76D is operated instantaneously, while it is decreased stepwise every time the upshift paddle 76U is operated instantaneously.

In SA3 corresponding to the automatic release determination unit 112, it is determined whether or not the manual shift mode is automatically canceled by the shift mode switching unit 106, that is, whether or not the manual shift mode is automatically released. Is done. The manual shift mode that is automatically released is a travel mode in which a virtual manual shift of the power transmission device 10 is performed in response to the operation of the paddle 76 when the shift position _PSH is the D position. It may be called a D paddle as shown in FIG. If the determination of SA3 is affirmative, that is, if the manual shift mode is automatically canceled, the process proceeds to SA4. On the other hand, if the determination at SA3 is negative, the operation goes to SA5.

  In SA4 corresponding to the manual shift mode control means 108, the setting of the engine lower limit rotational speed NLe is canceled, and at the same time, the slow rotational speed change process is executed when the engine rotational speed Ne is reduced. Then, after the execution of the rotational speed gradual change process is completed, the traveling state in which the engine lower limit rotational speed NLe is not set continues.

  In SA5 corresponding to the manual shift mode control means 108, the setting of the engine lower limit rotational speed NLe is released, and the engine rotational speed Ne is immediately reduced without executing the above rotational speed slow change process. Thereafter, the traveling state in which the engine lower limit rotational speed NLe is not set continues.

According to the present embodiment, the manual shift mode control means 108 sets the engine lower limit rotational speed NLe when a predetermined manual shift mode selection operation (manual setting operation) is performed by the occupant. Then, the manual shift mode control means 108 releases the setting of the engine lower limit rotation speed NLe and lowers the engine rotation speed Ne, so that the engine rotation speed Ne is made slower than a predetermined engine rotation speed change gradient ΔNe. The rotational speed slow change process to be reduced is executed. Accordingly, when the setting of the engine lower limit rotational speed NLe is cancelled, the change in the engine rotational speed Ne is moderated, and accordingly, the rotational speed change of the first electric motor M1 is also moderated. That is, the inertia generated according to the rotational acceleration of the first electric motor M1 (corresponding to dω _M1 / dt in the equation (1)) approaches zero as compared with the case where the rotational speed slow change process is not executed. It is possible to suppress the driving force loss. And possibility that the passenger | crew will be given the uncomfortable feeling resulting from the driving force omission is reduced.

  Further, according to the present embodiment, (a) the upshift paddle 76U and the downshift paddle 76D, which are the manual operation members, are provided in the steering device 70, and (b) the transmission mode control means 108 is provided with the engine lower limit rotation. In the traveling state in which the speed NLe is set, that is, in the manual shift mode, the engine lower limit rotational speed NLe is changed stepwise every time the upshift paddle 76U or the downshift paddle 76D is operated instantaneously, and (c) The manual transmission mode selection operation (manual setting operation) is that the upshift paddle 76U or the downshift paddle 76D is operated by the occupant in the automatic transmission mode of the D position. Accordingly, the occupant performs the manual shift mode selection operation in the same manner as an operation for switching the engine lower limit rotational speed NLe that has already been set, that is, an operation by the occupant performing a virtual manual shift of the power transmission device 10. Therefore, it is possible to easily perform the manual transmission mode selection operation without requiring a separate operation. Further, since the upshift paddle 76U and the downshift paddle 76D are provided in the steering device 70, the occupant (driver) sets and switches the engine lower limit rotational speed NLe while steering the vehicle 6 in the traveling direction. It can be done easily.

  Further, according to this embodiment, the manual release control is such that when the manual shift mode release operation (manual release operation) is performed, the setting of the engine lower limit rotational speed NLe is canceled and the engine rotational speed Ne is immediately reduced. It is. On the other hand, the automatic release control cancels the setting of the engine lower limit rotational speed NLe and slows down the rotational speed when the manual shift mode release operation is not performed and the manual shift mode release condition (automatic release condition) is satisfied. The change process is executed. The rotational speed gradual change process performed at the time of the automatic release control gradually decreases the engine rotational speed Ne as compared with the time of the manual release control. Here, since the manual shift mode canceling operation by the occupant is accompanied at the time of the manual canceling control, the occupant recognizes that the loss of the driving force is caused by his own operation and does not feel uncomfortable. On the other hand, since the setting of the engine lower limit rotation speed NLe is automatically released during the automatic release control, the occupant tends to feel uncomfortable if the driving force is lost. Further, from the viewpoint of improving fuel efficiency, it is preferable to remove the restriction on the engine lower limit rotational speed NLe at an early stage to lower the engine rotational speed Ne if it is not necessary to increase the engine rotational speed Ne. Accordingly, during the manual release control, the engine speed is reduced earlier than in the automatic release control, so that it is possible to improve the fuel consumption of the vehicle while avoiding the passenger from feeling uncomfortable. . Further, at the time of the automatic release control, when the engine rotational speed Ne is decreased, the rotational speed slow change process is executed, so that the driving force loss is suppressed.

Further, according to the present embodiment, the manual shift mode cancellation condition (automatic cancellation condition) is that neither the upshift paddle 76U nor the downshift paddle 76D is operated, and the accelerator opening Acc is determined in advance. This is established when the running state that is equal to or greater than the determination value LAcc continues for a predetermined determination time TIME _RL . Therefore, when it is estimated that the occupant has lost the intention to continue setting the engine lower limit rotational speed NLe after the manual shift mode selection operation, that is, the intention to continue the manual shift mode, the manual shift mode release condition is satisfied. Therefore, it is possible to automatically cancel the setting of the engine lower limit rotational speed NLe in accordance with the intention of the occupant.

  Further, according to the present embodiment, when the manual shift mode selection operation is performed by the occupant, the manual shift mode control means 108 sets the engine lower limit rotation speed NLe to be equal to or higher than the engine rotation speed Ne before the manual shift mode selection operation. Set. Therefore, the occupant can immediately increase the engine speed Ne before the operation by the manual shift mode selection operation, so that the acceleration response when the accelerator is depressed can be quickly improved.

  As mentioned above, although the Example of this invention was described in detail based on drawing, this is an embodiment to the last, and this invention is implemented in the aspect which added various change and improvement based on the knowledge of those skilled in the art. Can do.

  For example, in the above-described embodiment, the engine rotational speed change gradient ΔNe is determined by the amount of decrease per unit time of the engine rotational speed Ne, but the execution time of the rotational speed slow change process for decreasing the engine rotational speed Ne. Specifically, it may be determined by the elapsed time from time t1 to time t2 in the time chart of FIG.

  In FIG. 4 of the above-described embodiment, the upshift paddle 76 and the downshift paddle 78 are provided in the steering column 72. However, it is not necessary to be a paddle type manual operation member. Instead of the downshift paddle 78, an upshift button corresponding to the upshift paddle 76 and a downshift button corresponding to the downshift paddle 78 may be provided on the steering wheel 74.

  In the above-described embodiment, the engine lower limit rotation speed NLe is set in the manual shift mode, while the engine lower limit rotation speed NLe is canceled by switching from the manual shift mode to the automatic shift mode. The engine lower limit rotational speed NLe may be set regardless of the travel mode (shift mode). Furthermore, when the engine lower limit rotational speed NLe is set regardless of the travel mode, the setting of the engine lower limit rotational speed NLe is canceled, and the slow rotational speed change process may be executed. There is no problem.

  In the above-described embodiment, the manual shift mode selection operation is that the upshift paddle 76U or the downshift paddle 76D is operated in the automatic transmission mode of the D position. In addition, the operation other than the paddle 76 may be the manual shift mode selection operation. For example, a pushbutton switch that is pushed by the occupant to switch the travel mode is provided at a position where the driver who is the occupant can easily operate, and the travel mode is changed to the automatic transmission mode every time the pushbutton switch is operated. And the manual shift mode are alternately switched, and the manual shift mode selection operation may be that the pushbutton switch is pressed in the automatic shift mode of the D position.

  In the above-described embodiment, the engine lower limit rotational speed NLe is changed stepwise every time the paddle 76 is operated instantaneously in the manual shift mode, but this is changed after the engine lower limit rotational speed NLe is set. It is not essential to obtain the effect of the rotational speed slow change process.

  In the first planetary gear device 20 of the above-described embodiment, the first carrier CA1 is connected to the engine 14, the first sun gear S1 is connected to the first electric motor M1, and the first ring gear R1 is connected to the output gear 24. However, the connection relationship is not necessarily limited thereto, and the engine 14, the first electric motor M1, and the output gear 24 are respectively connected to the three rotating elements CA1, S1, and R1 of the first planetary gear device 20. It can be connected to any of them.

  In the above-described embodiment, the second planetary gear unit 22 is interposed between the output gear 24 and the second electric motor M2, but there is no second planetary gear unit 22 and the second electric motor M2 is the output gear 24. It can be directly connected to the cable.

  In the above-described embodiment, the ring gear R2 of the second planetary gear device 22 is integrally connected to the ring gear R1 of the first planetary gear device 20, but the connection destination of the ring gear R2 is connected to the ring gear R1. For example, the first planetary gear device 20 may be connected to the first carrier CA1 without being limited thereto. Further, the ring gear R2 may be connected to somewhere in the power transmission path between the first planetary gear device 20 and the drive wheel 40 instead of the ring gear R1.

  Further, in the above-described embodiment, the second electric motor M2 is provided in the vehicle drive device 8, and is connected to the drive wheel 40 as the front wheel via the second planetary gear device 22 and the like so as to be able to transmit power. However, a vehicle configuration in which the second electric motor M2 is not provided in the vehicle drive device 8 is also conceivable. For example, a vehicle configuration in which the second electric motor M2 is provided separately from the vehicle drive device 8 and the second electric motor M2 is connected to the rear wheels so that power can be transmitted is also conceivable.

  In the above-described embodiment, the vehicle drive device 8 includes the second planetary gear device 22 in a part of the power transmission path between the second electric motor M2 and the drive wheel 40. The device 22 may be replaced with a gear device composed of a pair of gears that are not planetary gear devices.

  In the above-described embodiment, no transmission is provided in the power transmission path between the output gear 24 and the drive wheel 40, but a manual transmission or an automatic transmission is provided in the power transmission path. There is no problem.

  In the above-described embodiment, when the shift mode switching unit 106 switches the travel mode from the automatic shift mode to the manual shift mode, the manual shift mode control unit 108 rotates the engine before switching to the manual shift mode. The engine lower limit rotational speed NLe is set to be equal to or higher than the speed Ne, but the engine lower limit rotational speed NLe immediately after switching to the manual shift mode may not be equal to or higher than the engine rotational speed Ne before the switching. For example, the virtual shift stage that is initially selected after switching from the automatic shift mode to the manual shift mode is set to a predetermined shift stage in advance, and the engine lower limit rotational speed NLe immediately after switching to the manual shift mode is It may be set based on the vehicle speed V from the engine lower limit rotational speed map of FIG.

  In the above-described embodiment, the first planetary gear unit 20 functions as an electric continuously variable transmission whose gear ratio is continuously changed by controlling the operating state of the first electric motor M1. However, for example, the gear ratio of the first planetary gear device 20 may be changed stepwise by using a differential action instead of continuously.

  In the power transmission device 10 of the above-described embodiment, the engine 14 is connected to the input shaft 18 via the damper 16. A power interrupting device such as a clutch is interposed between the engine 14 and the input shaft 18. It does not matter.

  In FIG. 1 of the above-described embodiment, the power interrupting device is not interposed between the first electric motor M1 and the first sun gear S1 and between the second electric motor M2 and the output gear 24. The power interrupting device may be interposed in either or both of them.

  In the above-described embodiment, the first planetary gear device 20 and the second planetary gear device 22 are both single planetary, but one or both of them may be double planetary.

  In the above-described embodiment, the engine 14 is connected to the first carrier (first rotating element) CA1 constituting the first planetary gear device 20 so as to be able to transmit power, and is connected to the first sun gear (second rotating element) S1. The first electric motor M1 is connected so as to be able to transmit power, and a power transmission path to the drive wheels 40 is connected to the first ring gear (third rotating element) R1. In the configuration in which the two planetary gear devices are connected to each other by a part of the rotating elements constituting the planetary gear device, an engine, an electric motor, and a driving wheel are respectively connected to the rotating elements of the planetary gear device. The power transmission may be connected, and the structure may be switched between a stepped transmission and a continuously variable transmission by control of a clutch or a brake connected to a rotating element of the planetary gear device.

  The second electric motor M2 of the above-described embodiment is connected to the output gear 24 that constitutes a part of the power transmission path from the engine 14 to the driving wheel 40 via the second planetary gear unit 22, In addition to the electric motor M2 being connected to the output gear 24, the electric motor M2 can also be connected to the first planetary gear device 20 via an engagement element such as a clutch. The second electric motor is used instead of the first electric motor M1. The power transmission device 10 may be configured such that the differential state of the first planetary gear device 20 can be controlled by M2.

8: Vehicle drive device 14: Engine 20: First planetary gear device (differential mechanism)
40: Drive wheel 70: Steering device 76U: Upshift paddle (manual operation member)
76D: Downshift paddle (manual operation member)
100: Electronic control device (control device)
M1: First motor (differential motor)

Claims (4)

In a vehicle drive device comprising an engine and a differential mechanism that constitutes a part of a power transmission path between the engine and drive wheels and whose differential state is controlled by a differential motor, A control device for a vehicle drive device that sets an engine lower limit rotation speed when a manual setting operation is performed,
When releasing the setting of the engine lower limit rotational speed and lowering the engine rotational speed, a rotational speed gradual change process for gradually decreasing the engine rotational speed from a predetermined engine rotational speed change gradient is executed. A control device for a vehicle drive device. The manual operation member operated by the occupant is provided in a steering device for steering the traveling direction of the vehicle,
In the traveling state in which the engine lower limit rotation speed is set, the engine lower limit rotation speed is changed every time the manual operation member is operated,
2. The vehicle drive device control according to claim 1, wherein the manual setting operation is that the occupant operates the manual operation member in a traveling state in which the engine lower limit rotation speed is not set. apparatus. While performing a manual release control to release the setting of the engine lower limit rotation speed when a predetermined manual release operation is performed by the occupant, the manual release operation is not performed and a predetermined automatic release condition is satisfied Automatic release control to release the setting of the engine lower limit rotational speed in case
3. The vehicle according to claim 2, wherein the slow rotation speed change process is performed during the automatic release control, and the engine rotational speed is gradually reduced as compared with the manual release control. Drive device controller. The automatic release condition is satisfied when the manual operation member is not operated and a traveling state in which an accelerator opening is equal to or greater than a predetermined accelerator opening determination value continues for a predetermined determination time. The control device for a vehicle drive device according to claim 3.

Images