JPH10290502A - Creep torque controller - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suitably prevent the backward movement of a vehicle, even when the backward movement of the vehicle is not able to be inhibited mechanically when the vehicle is stopped in a forward range. SOLUTION: When a second transmission position (2nd) is selected and the backward movement of a vehicle is mechanically inhibited by means of a one- way clutch (SA9), the burden of a motor generator is reduced and the energy efficiency of the motor is improved, because the motor torque TM which is required to generate creep torque is reduced from an ordinary condition or to nearly zero (SA10). On the other hand, when a first transmission position (1st) is selected and the backward movement of the vehicle is not mechanically inhibited (SA11), the backward movement of the vehicle is suitably prevented on a slope, because the motor torque TM is increased (SA12).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a creep torque control device for controlling a creep torque of a vehicle.

[0002]

2. Description of the Related Art In various vehicles such as an electric drive vehicle having an electric motor as a power source, or a hybrid vehicle having an engine and an electric motor as a power source, it is necessary to prevent the vehicle from moving backward when the vehicle is stopped on a slope. Japanese Patent Laid-Open Publication No. Hei 6 (1994) -112605 discloses a technique in which the engagement state of each friction engagement device of a power transmission device for transmitting power from a power source to a drive wheel is switched to mechanically inhibit reverse rotation of the drive wheel by a one-way clutch. No. 78417. On the other hand, a vehicle having a creep torque control device that activates a power source to generate a predetermined creep torque on drive wheels even when the accelerator pedal is not depressed (accelerator OFF state) for the purpose of, for example, facilitating starting on a slope. Has been proposed.

[0003]

However, in such a technique, when a solenoid valve or the like for controlling the engagement state of each friction engagement device of the power transmission device breaks down, the one-way clutch drives the drive wheels. There was a possibility that it would not be possible to prohibit the reversal.

The present invention has been made in view of such circumstances, and an object of the present invention is to provide a vehicle which is not mechanically prohibited from reversing when the vehicle is stopped on a slope by a vehicle reversal prohibiting means. It is an object of the present invention to provide a creep torque control device in which reverse running of a vehicle is suitably prevented.

[0005]

In order to achieve the above object, a first aspect of the present invention provides a driving range in which a driving force is generated by operating a power source in accordance with an accelerator operation amount. A creep torque control device that operates a power source to generate a predetermined creep torque on drive wheels even when an accelerator is in an OFF state, comprising: (a) a vehicle reverse device that mechanically prohibits the vehicle from reversing when the vehicle stops in the travel range. And (b) creep torque changing means for changing the creep torque according to whether or not the vehicle reverse movement is prohibited by the vehicle reverse movement prohibiting means.

In a second aspect based on the first aspect, the power source is an electric motor.

[0007]

According to the present invention, the creep torque is changed by the creep torque changing means depending on whether or not the reverse movement of the vehicle is prohibited by the reverse means of the vehicle. In this case, the creep torque is reduced or set to zero, so that the load on the power source is reduced and the energy efficiency such as fuel efficiency is improved. In addition, when the reverse movement of the vehicle is not prohibited, the reverse movement of the vehicle on the slope is preferably prevented by increasing the creep torque.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Here, a creep torque control device for generating a creep torque by an electric motor only has to control, for example, a motor torque, and a creep torque control device for generating a creep torque in an engine is, for example, a torque converter or the like. When the engine has a predetermined output, the transmission torque (engagement torque) of the friction clutch can be reduced while operating the engine at the predetermined output. You only have to control it. A first rotating element connected to the engine, a second rotating element connected to the electric motor, and a third rotating element connected to the output member, and mechanically combine forces therebetween; In the case of having an electric torque converter provided with a composite distribution mechanism such as a planetary gear device for distributing, the reaction torque of the electric motor may be controlled while operating the engine at a predetermined output.

The creep torque changing means includes a creep torque reducing means for reducing or zeroing the creep torque when the vehicle is prohibited from reversing by, for example, the vehicle reversing prohibiting means. When the reverse movement of the vehicle is not prohibited by the means, it is constituted by a creep torque increasing means for increasing the creep torque.

The vehicle reversing prohibiting means converts any power transmission member (such as a rotating element of an automatic transmission) from a power source to a drive wheel to a position-fixed member such as a housing via a one-way clutch. It is configured to include an engaging device such as a brake or a clutch to be connected. For example, a plurality of forward gears having different gear ratios are established depending on the operation states of the plurality of frictional engagement devices, and when the vehicle is prevented from moving backward by a one-way clutch at a predetermined gear, the predetermined gear ratio is determined when the vehicle stops. It is configured to establish a gear.

The reverse movement of the vehicle when the vehicle is stopped means that the vehicle is traveling backward when the forward range in which the vehicle is allowed to travel forward is selected by the shift selection operation means, and the vehicle is backward traveled by the shift selection operation means. This is forward movement when the reverse range is selected, and the present invention can be applied to both of them. However, it is also possible to prohibit only one of them, for example, prohibiting reverse when the vehicle is stopped in the forward range. The forward range and the reverse range correspond to the running range. The case where the vehicle is not prohibited from reversing by the vehicle reversing prohibiting means is that the hydraulic circuit for operating the engagement device, the solenoid valve for switching the hydraulic circuit is faulty, or the oil temperature of the automatic transmission is extremely low. In this case, the fluidity of the hydraulic oil is poor, and a shift shock is likely to occur when the predetermined gear is established, and it is not appropriate to establish the gear.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a skeleton diagram of a hybrid drive device 10 of a hybrid vehicle including a creep torque control device according to one embodiment of the present invention.

In FIG. 1, a hybrid drive unit 10 is for an FR (Front Engine / Rear Drive) vehicle, and functions as an engine 12 such as an internal combustion engine that operates by burning fuel, and functions as an electric motor and a generator. A motor generator 14, a single-pinion type planetary gear set 16, and an automatic transmission 18 are provided along the front-rear direction of the vehicle, and are driven right and left from an output shaft 19 via a propeller shaft (not shown) and a differential unit. The driving force is transmitted to the driving wheels (rear wheels). The planetary gear unit 16 is a composite distribution mechanism for mechanically distributing and distributing force. The planetary gear unit 16 constitutes an electric torque converter 24 together with the motor generator 14, and a ring gear 16r as a first rotating element includes a first clutch C
Coupled to the engine 12 via the E _1, sun gear 16s of the second rotating element is connected to the rotor shaft 14r of the motor generator 14, the automatic transmission 18 carrier 16c of the third rotating element that serves as an output member It is connected to the input shaft 26. Further, the sun gear 16s and the carrier 16c is adapted to be connected by the second clutch CE _2. In this embodiment, the engine 1
2, motor generator 14, and planetary gear set 16
And the automatic transmission 18 corresponds to a power transmission device that transmits power from the power source to the drive wheels.

[0014] The output of the engine 12 is transmitted rotation fluctuation and the flywheel 28 and the spring for suppressing the torque variation, the first clutch CE ₁ via a damper device 30 by the elastic member such as rubber. Each of the first clutch CE ₁ and the second clutch CE ₂ is a friction type multi-plate clutch that is engaged and released by a hydraulic actuator.

The automatic transmission 18 is a combination of an auxiliary transmission 20 composed of a front type overdrive planetary gear unit and a main transmission 22 having four forward and one reverse stages composed of a simple connection of three planetary gear trains. . More specifically, the auxiliary transmission 20 includes a single pinion type planetary gear set 32, a hydraulic clutch C ₀ , a brake B _0, which is frictionally engaged by a hydraulic actuator, and a one-way clutch F _0. Have been. The main transmission 22 includes a third set of single-pinion type planetary gear unit 34, 36, 38, clutch C ₁ hydraulic that are frictionally applied by hydraulic actuators, C _2, the brake B _1, B _2, B ₃ and B ₄ and one-way clutches F ₁ and F ₂
It is comprised including.

The hydraulic circuit 40 is energized and de-energized by the solenoid valves SL1 to SL4 shown in FIG.
Is switched, or the hydraulic circuit 40 is mechanically switched by a manual shift valve connected to a shift lever 42 as a shift selection operating means, so that the clutches C ₀ , C ₁ , C ₂ , the brakes B ₀ , B
₁ , B ₂ , B ₃ , B ₄ are respectively engaged and disengaged,
Neutral (N) and forward 5 as shown in FIG.
The speed stages (1st to 5th) and the reverse speed (Rev) are established. The shift lever 42 can select at least a D range as a forward range, an R range as a reverse range, and an N range as a neutral range that does not transmit power, and the D range and the R range correspond to the running range. doing. Note that the automatic transmission 18 and the electric torque converter 24 are configured substantially symmetrically with respect to a center line, and a lower half of the center line is omitted in FIG.

In the column of clutch, brake and one-way clutch in FIG. 3, "○" indicates engagement, and "●" indicates that the shift lever 42 is in the engine brake range, for example, "3", "2" and "L" ranges. Engaged when operated to the low speed range of
A blank indicates non-engagement. In this case, the neutral N, the reverse gear Rev, and the engine brake range are established by mechanically switching the hydraulic circuit 40 by a manual shift valve mechanically connected to the shift lever 42, and the forward gear Between the 1st to 5th of the solenoid valve SL
It is electrically controlled by 1 to SL4. Further, the speed ratio of the forward shift speed gradually decreases from 1st to 5th, and the 4th speed ratio i ₄ = 1. FIG. 3 shows an example of the gear ratio of each gear.

As shown in the operation table of FIG.
Shifting between the gear stage (2nd) and third shift stage (3rd) will clutch-changing the engagement-released state of the second brake B ₂ and the third brake B ₃ together.
In order to smoothly perform this shift, the circuit shown in FIG. 4 is incorporated in the hydraulic circuit 40 described above.

In FIG. 4, reference numeral 70 denotes a 1-2 shift valve, and reference numeral 71 denotes a 2-3 shift valve.
Reference numeral 72 indicates a 3-4 shift valve. The communication state of each port of these shift valves 70, 71, 72 at each shift speed is determined by the respective shift valves 70, 7
1 and 72 are shown below. The numbers indicate the respective gears.

A third brake B ₃ is connected to an oil passage 7 to a brake port 74 communicating with the input port 73 at the first and second shift speeds among the ports of the 2-3 shift valve 71.
5 are connected. This oil passage has an orifice 7
6 is interposed, the damper valve 77 is connected between the orifice 76 and the third brake B _3.
The damper valve 77 is configured to perform a buffering action by inhalation of a small amount of hydraulic pressure when the line pressure to the third brake B ₃ is rapidly supplied.

Further, reference numeral 78 is a B-3 control valve has a third engaging pressure of the brake B ₃ to be directly controlled by the B-3 control valve 78. That is, the B-3 control valve 78
Is provided with a spool 79, a plunger 80, and a spring 81 interposed therebetween, and an oil passage 75 is connected to an input port 82 opened and closed by the spool 79,
The output port 83 to be brought selectively communicating with the input port 82 is connected to the third brake B _3. Further, the output port 83 is connected to a feedback port 84 formed on the distal end side of the spool 79.

On the other hand, among the ports of the 2-3 shift valve 71, a port 86 for outputting the D range pressure at the third or higher speed is connected to an oil passage 85. It is communicated via 87. Further, a linear solenoid valve SLU is connected to a control port 88 formed on the end side of the plunger 80.

Therefore, the B-3 control valve 7
8, the pressure adjustment level is set by the elastic force of the spring 81 and the hydraulic pressure supplied to the port 85, and the elastic force by the spring 81 increases as the signal pressure P _SLU supplied to the control port 88 increases. It is configured.

Further, reference numeral 89 in FIG.
The 2-3 timing valve 89 includes a spool 90 having a small-diameter land and two large-diameter lands, a first plunger 91, and a spring 92 and a spool 90 disposed therebetween. First
And a second plunger 93 disposed on the opposite side to the plunger 91 of the second embodiment.

An oil passage 95 is connected to a port 94 at an intermediate portion of the 2-3 timing valve 89.
Reference numeral 5 denotes a port of the 2-3 shift valve 71 which is connected to a port 96 which is communicated with the brake port 74 at the third or higher speed.

Further, the oil passage 95 branches on the way.
Port 9 opening between the small land and the large land
7 is connected via an orifice. A port 98 selectively connected to the intermediate port 94 is connected to a solenoid relay valve 100 via an oil passage 99.

[0027] Then, the linear solenoid valve SLU is connected to the port that is open to an end portion of the first plunger 91, also the second brake B ₂ is an orifice to a port that opens to the end of the second plunger 93 Connected through.

[0028] The oil passage 87 is for the purpose of supplying and discharging the hydraulic pressure to the second brake B _2, a small diameter orifice 101 and a check ball with the orifice 102 is interposed in the midway. Further, the oil passage 103 branched from the oil passage 87, the large-diameter orifice 1 having a check ball to open when the pressure discharged from the second brake B ₂
The oil passage 103 is connected to an orifice control valve 105 described below.

The orifice control valve 105 is a valve for controlling the exhaust圧速degree from the second brake B _2, the port 107 formed in an intermediate portion to be opened and closed by the spool 106 and the second brake B _Two
The oil passage 103 is connected to a port 108 formed below the port 107 in the figure.

Port 1 to which the second brake B ₂ is connected
The port 109 formed on the upper side in FIG. 7 is a port selectively communicated with the drain port. The port 109 is connected to the port 111 of the B-3 control valve 78 via an oil passage 110. It is connected. Incidentally, this port 111 is a port that is not selectively communicating the output port 83 is connected to the third brake B _3.

A control port 112 formed at the end of the port of the orifice control valve 105 opposite to the spring for pressing the spool 106 is connected to a port 114 of the 3-4 shift valve 72 via an oil passage 113. ing. This port 114 outputs the signal pressure of the third solenoid valve SL3 at a speed lower than the third speed,
Further, it is a port for outputting a signal pressure of the fourth solenoid valve SL4 at a speed higher than the fourth speed.

Further, an oil passage 115 branched from the oil passage 95 is connected to the orifice control valve 105, and the oil passage 115 is selectively connected to a drain port.

In the 2-3 shift valve 71, a port 116 for outputting the D-range pressure at a speed lower than the second speed is opened at a portion of the 2-3 timing valve 89 where a spring 92 is disposed. The port 117 is connected via an oil passage 118. A port 119 of the 3-4 shift valve 72 which is communicated with the oil passage 87 at a speed lower than the third speed is connected to the solenoid relay valve 100 via an oil passage 120.

In FIG. 4, reference numeral 121 denotes the second
Indicates an accumulator for the brake B _2, accumulator control pressure P _ac the linear solenoid valve SLN is pressure regulated in accordance with the hydraulic pressure output is supplied to the back pressure chamber. This accumulator control pressure P
_ac is configured such that the lower the output pressure of the linear solenoid valve SLN, the higher the pressure. Therefore,
The transient hydraulic pressure P _B2 for engagement / disengagement of the second brake B ₂ is
The lower the signal pressure of the linear solenoid valve SLN, the higher the pressure. An accumulator is also provided in the other clutches C ₁ and C ₂ for shifting, the brake B _{0, and the} like, and the accumulator control pressure _Pac is applied so that the transient hydraulic pressure during shifting changes the input shaft 2.
6 is controlled in accordance with the torque or the like.

Further, reference numeral 122 denotes a C-0 exhaust valve, and further reference numeral 123 denotes an accumulator for the clutch C _0. C-0 exhaust valve 1
22 is to operate to engage the clutch C ₀ in order to engine brake only at the second gear of the second speed range.

Therefore, according to the hydraulic circuit 40 described above, if the port 111 of the B-3 control valve 78 is in communication with the drain, the engagement pressure P of the third brake B _3
B3 can be directly regulated by the B-3 control valve 78, and the pressure regulation level can be changed by the linear solenoid valve SLU.

The orifice control valve 10
5 of the spool 106, if the position shown in the left half of the figure, the second brake B ₂ allows ejection pressure through the orifice control valve 105, thus second
It is possible to control the drain rate from the brake B _2.

Further, when shifting from the second gear to the third gear, the third brake B ₃ is gradually released and the second gear is released.
But not so-called clutch-to-clutch shifting gently engage the brake B ₂ is carried out, the third release transitional hydraulic pressure of the brake B ₃ which is driven by the linear solenoid valve SLU based on the input shaft torque to the input shaft 26 By controlling P _B3 , shift shock can be reduced appropriately. The control of the hydraulic pressure P _B3 based on the input shaft torque can be performed in real time by feedback control or the like, but may be performed based only on the input shaft torque at the start of shifting.

As shown in FIG. 2, the hybrid drive device 10 includes a controller 50 for hybrid control and a controller 52 for automatic transmission control. Each of these controllers 50 and 52 includes a microcomputer having a CPU, a RAM, a ROM, and the like, and includes a shift position sensor 62, a brake switch 64, a vehicle speed sensor 65, an accelerator operation amount sensor 66, an oil temperature sensor 6,
7, the operation range of the shift lever 42, the ON / OFF of the foot brake, the vehicle speed V (corresponding to the rotation speed N _O of the output shaft 19 of the automatic transmission 18), the accelerator operation amount θ _AC ,
A signal indicating the oil temperature of the hydraulic circuit 40 is supplied, and the rotation speed N _I of the input shaft 26 of the automatic transmission 18 and the engine torque T
Information about _E , motor torque T _M , engine speed N _E , motor speed N _M , and the amount of charge SOC of the power storage device 58 (see FIG. 5) are supplied from various detection means. Perform signal processing according to a preset program. The engine torque T _E is determined from a throttle valve opening and the fuel injection amount, the motor torque T _M is determined from a motor current, the electricity storage amount SOC is Ya motor current during charging motor generator 14 functions as a generator Required from charging efficiency.

The output of the engine 12 is controlled in accordance with the operation state such as the accelerator operation amount θ _AC by controlling the throttle valve opening, the fuel injection amount, the ignition timing and the like by the hybrid control controller 50. . As shown in FIG. 5, the motor generator 14 is connected to a power storage device 5 such as a battery via an M / G controller (inverter) 56.
8 and a rotational driving state in which electric energy is supplied from the power storage device 58 by the hybrid control controller 50 and is rotationally driven at a predetermined torque, and a regenerative braking (electric braking of the motor generator 14 itself). With the torque, the power storage device 58 is switched between a charging state in which the power storage device 58 is charged with electric energy and a no-load state in which the rotor shaft 14r is allowed to rotate freely. The first clutch CE ₁ and the second clutch CE ₂ are switched between the engaged and disengaged states by the hybrid controller 50 switching the hydraulic circuit 40 via an electromagnetic valve or the like. The automatic transmission 18 includes an automatic transmission control controller 5.
2, the excitation states of the solenoid valves SL1 to SL4 and the linear solenoid valves SLU, SLT, SLN are controlled, and the hydraulic circuit 40 is switched or the hydraulic control is performed, so that the shift speed is switched according to a predetermined shift condition. Can be The shift conditions are set, for example, by a shift map or the like that uses the running state such as the accelerator operation amount θ _AC and the vehicle speed V as parameters.

The hybrid control controller 50
For example, Japanese Patent Application No. 7-294 filed earlier by the applicant of the present application
As described in No. 148, one of the nine operation modes shown in FIG. 7 is selected according to the flowchart shown in FIG. 6, and the engine 12 and the electric torque converter 24 are operated in the selected mode. The hybrid control controller 50 corresponds to the creep torque control device, and when the modes 1 and 5 are selected, a signal is generated so that the motor generator 14 is operated even when the accelerator is off to generate a predetermined creep torque on the drive wheels. Perform processing.

In FIG. 6, in step S1, it is determined whether or not an engine start request has been made, for example, to drive the engine 12 as a power source or to rotate the motor generator 14 by the engine 12 to charge the power storage device 58. Then, it is determined whether or not a command to start the engine 12 has been issued. Here, if there is a start request, mode 9 is selected in step S2. Mode 9, the first clutch CE ₁ engaged (ON) As is apparent from FIG. 7, the second
The clutch CE ₂ engaged (ON), while rotating the engine 12 through the planetary gear 16 by the motor generator 14 performs the engine start control of the fuel injection to start the engine 12.

[0043] This mode 9, at the time of vehicle stop is performed by the automatic transmission 18 in neutral, only the motor-generator 14 first releases the clutch CE ₁ as mode 1 during running of the power source, first Clutch CE
₁ is engaged, the motor generator 14 is operated with an output higher than the required output required for traveling, and the engine 12 is rotationally driven with a margin output higher than the required output. Further, even when the vehicle is running, it is possible to temporarily execute the mode 9 with the automatic transmission 18 in the neutral state. By starting the engine 12 by the motor generator 14 in this manner, a starter (electric motor or the like) dedicated to starting is unnecessary, the number of parts is reduced, and the apparatus is inexpensive.

On the other hand, if the determination in step S1 is denied, that is, if there is no engine start request, step S3 is executed to determine whether there is a request for braking force, for example, whether the brake is ON. Or shift lever 42
Is an engine brake range such as L or 2 (a range in which shift control is performed only at a low shift speed and engine brake and regenerative braking are applied), and whether an accelerator operation amount θ _AC is 0 or simply It is determined by whether the operation amount θ _AC is 0 or not.

If this determination is affirmative, step S
Execute Step 4. In step S4, it is determined whether or not the state of charge SOC of power storage device 58 is equal to or greater than a predetermined maximum state of charge B. If SOC ≧ B, mode 8 is selected in step S5, and if SOC <B, step 8 is selected. Mode 6 is selected in S6. The maximum power storage amount B is the maximum power storage amount allowed to charge the power storage device 58 with electric energy, and is set to a value of, for example, about 80% based on the charging / discharging efficiency of the power storage device 58 and the like.

Mode 8 selected in step S5
As shown in FIG. 7, the first clutch CE ₁ is engaged (ON), the second clutch CE ₂ is engaged (ON), the motor generator 14 is in a no-load state, and the engine 12
Is stopped, that is, the throttle valve is closed, and the fuel injection amount is set to 0, whereby the braking force due to the rubbing rotation of the engine 12, that is, the engine brake is applied to the vehicle, and the brake operation by the driver is reduced. Driving operation becomes easy. Further, since motor generator 14 is set in a no-load state and is freely rotated, it is possible to avoid a situation where power storage amount SOC of power storage device 58 becomes excessive and impairs performance such as charge / discharge efficiency.

[0047] Mode 6 is selected in step S6, disengaging the first clutch CE ₁ As apparent from FIG. 7 (OF
F), the second clutch CE ₂ is engaged (ON), the engine 12 is stopped, and the motor generator 14 is charged, and the motor generator 14 is rotationally driven by the kinetic energy of the vehicle. Since the power storage device 58 is charged and a regenerative braking force such as an engine brake is applied to the vehicle, the braking operation by the driver is reduced and the driving operation is facilitated.

Further, since the first clutch CE ₁ is released and the engine 12 is shut off, there is no energy loss due to rubbing of the engine 12 and the operation is executed when the state of charge SOC is smaller than the maximum state of charge B. Therefore, the amount of charge SOC of the power storage device 58 does not become excessive and the performance such as charge / discharge efficiency is not impaired.

On the other hand, if the judgment in step S3 is negative, that is, if there is no request for the braking force, step S7 is executed.
And whether or not engine start is requested is determined by, for example, whether or not the vehicle is stopped during traveling using the engine 12 as a power source such as mode 2 or mode 3, that is, whether or not the vehicle speed V ≒ 0. to decide.

If this judgment is affirmed, step S8 is executed. In step S8, the shift lever 42
It is determined whether the “P” range or the “N” range, which is the non-drive range, has been selected, and if the “P” range or the “N” range has not been selected, ie, the “D” range or the “R” range, If a driving range such as the "range" is selected, mode 5 is selected in step S9, and "P"
If the range or the "N" range has been selected, mode 7 is selected in step S10.

Mode 5 selected in step S9
Is a first clutch CE ₁ As apparent from FIG. 7 engaged (ON), and second releasing clutch CE ₂ (OFF),
With the engine 12 in the operating state, the motor generator 14
The vehicle is started by controlling the regenerative braking torque (reaction torque) of the vehicle. The predetermined regenerative braking torque is set so that a predetermined creep torque can be obtained even when the accelerator is OFF, that is, even when the accelerator operation amount θ _AC is substantially zero. Generated.

More specifically, assuming that the gear ratio of the planetary gear set 16 is ρ _E , the engine torque T _E : the output torque of the planetary gear set 16: the motor torque T _M = 1: (1+
ρ _E ): ρ _E. For example, if the gear ratio ρ _E is set to about 0.5 which is a general value, the motor generator 14 shares half of the engine torque T _E , so that the engine torque T A torque about 1.5 times _E is output from the carrier 16c. That is, a high torque start of (1 + ρ _E ) / ρ _E times the torque of motor generator 14 can be performed. Also, if the motor current is cut off to put the motor generator 14 in a no-load state,
The carrier 16 is rotated only by rotating the rotor shaft 14r in the reverse direction.
The output from c becomes 0, and the vehicle stops (creep torque = 0). That is, the planetary gear device 1 in this case
Numeral 6 functions as a starting clutch and a torque amplifying device. By gradually increasing the motor torque (regenerative braking torque) T _M to increase the reaction force, the output torque is (1 + ρ _E ) times the engine torque T _E. The vehicle can be started smoothly.

Here, in this embodiment, a motor generator having a torque capacity approximately ρ _E times the maximum torque of the engine 12, that is, a motor generator 14 as small and small as possible while ensuring the required torque is used. ,
The device is compact and inexpensive. In this embodiment, the output of the engine 12 is increased by increasing the throttle valve opening and the fuel injection amount in response to the increase in the motor torque T _M. thereby preventing engine stall or the like due to the reduction in the number N _E.

Mode 7 selected in step S10 includes:
As can be appreciated the first clutch CE ₁ engages from FIG 7 (O
N), and second releasing clutch CE ₂ and (OFF), the engine 12 as a driving state, in which the electrically neutral motor-generator 14 as a no-load condition, the rotor shaft 14r is opposite direction of the motor-generator 14 The rotation of the input shaft 2 of the automatic transmission 18
The output for 6 becomes zero. Thus, it is not necessary to stop the engine 12 one by one when the vehicle is stopped while traveling using the engine 12 as a power source, such as in mode 2 or mode 3, and the engine can be started in mode 5 substantially.

On the other hand, if the determination in step S7 is denied, that is, if there is no request to start the engine, step S11 is executed, and the required output Pd is set to the first preset value.
It is determined whether the value is equal to or less than the determination value P1. The required output Pd is an output necessary for the running of the vehicle including the running resistance, and is the accelerator operation amount θ _AC , its changing speed, the vehicle speed V (output shaft rotation speed N _O ),
Based on the gear position of the automatic transmission 18 and the like, it is calculated by a predetermined data map, an arithmetic expression or the like.

The first judgment value P1 is a boundary value between a middle load region where the vehicle runs only using the engine 12 as a power source and a low load region where the vehicle runs only using the motor generator 14 as a power source. In consideration of the energy efficiency, the exhaust gas amount, the fuel consumption amount, and the like are determined by experiments and the like so as to be as small as possible.

If the determination in step S11 is affirmative,
That is, when the required output Pd is equal to or less than the first determination value P1, it is determined in step S12 whether or not the state of charge SOC is equal to or greater than the preset minimum amount of charge A. If SOC ≧ A, the mode 1 is determined in step S13. On the other hand, if SOC <A, mode 3 is selected in step S14. The minimum power storage amount A is a minimum power storage amount that is allowed to take out electric energy from power storage device 58 when traveling using motor generator 14 as a power source, and is, for example, 70% based on charge / discharge efficiency of power storage device 58 and the like. The value of degree is set.

[0058] The mode 1, the 7 released as apparent the first clutch CE ₁ from to (OFF), the second clutch CE ₂ engaged (ON), to stop the engine 12,
The motor generator 14 is driven to rotate at the required output Pd, and the vehicle is started or run using only the motor generator 14 as a power source. The motor generator 14 is operated (torque generation) with a predetermined output so that a predetermined creep torque is obtained even when the accelerator is OFF, that is, when the accelerator operation amount θ _AC is substantially zero. Even if the mode 1 is selected, because the engine 12 first clutch CE ₁ is released is interrupted, the mode 6 less similarly pulled rubbing loss, by appropriate shift control of the automatic transmission 18 Efficient motor drive control is possible. This mode 1 is executed when the required output Pd is in a low load region where the first determination value P1 or less and the state of charge SOC of the power storage device 58 is equal to or more than the minimum state of charge A.
Energy efficiency is higher than when the vehicle is driven by a power source, and fuel consumption and exhaust gas can be reduced. In addition, the state of charge SOC of the power storage device 58 becomes lower than the minimum state of charge A, which impairs performance such as charge and discharge efficiency. Absent.

The mode 3 selected in step S14 is
As is clear from FIG. 7, the first clutch CE ₁ and the second clutch CE ₁
The clutch CE ₂ is engaged (ON) together, the engine 12 is driven, the motor generator 14 is charged by regenerative braking, and is generated by the motor generator 14 while the vehicle is running at the output of the engine 12. Electric energy is charged in the power storage device 58. The engine 12 is operated at an output higher than the required output Pd, and the current control of the motor generator 14 is performed so that the motor generator 14 consumes a marginal power greater than the required output Pd.

On the other hand, if the determination in step S11 is negative, that is, if the required output Pd is larger than the first determination value P1, in step S15, the required output Pd is determined.
It is determined whether d is greater than the first determination value P1 and less than the second determination value P2, that is, whether P1 <Pd <P2. The second determination value P2 is a boundary value between a medium load region where the vehicle runs only using the engine 12 as a power source and a high load region where the vehicle runs using both the engine 12 and the motor generator 14 as a power source. In consideration of the energy efficiency, the exhaust gas amount and the fuel consumption amount are determined in advance by experiments and the like so as to minimize the amount.

If P1 <Pd <P2, it is determined whether or not SOC ≧ A in step S16. If SOC ≧ A, mode 2 is selected in step S17, and SOC <A
In the case of, mode 3 is selected in step S14.
If Pd ≧ P2, SOC ≧ A in step S18.
It is determined whether or not SOC is greater than or equal to A, and if SOC ≧ A, step S19
To select mode 4, and if SOC <A, then step S
At 17, mode 2 is selected.

In the mode 2, the first clutch CE ₁ and the second clutch CE ₂ are both engaged (ON), the engine 12 is operated at the required output Pd, and the motor generator 14 is operated, as is apparent from FIG. Under no load condition, the vehicle is run using only the engine 12 as a power source.

In the mode 4, the first clutch CE ₁ and the second clutch CE ₂ are both engaged (ON), the engine 12 is operated, and the motor generator 14 is driven to rotate. The vehicle is caused to travel at a high output using both of the generators 14 as power sources.
This mode 4 is executed in a high load region where the required output Pd is equal to or more than the second determination value P2. However, since the engine 12 and the motor generator 14 are used together, only one of the engine 12 and the motor generator 14 is used. Compared to running as a power source, energy efficiency is not significantly impaired, and fuel consumption and exhaust gas can be reduced.
Further, since the process is executed when the state of charge SOC is equal to or more than the minimum state of charge A, the state of charge SOC of the power storage device 58 is set to the minimum state of charge A.
The performance such as charge / discharge efficiency is not impaired.

To summarize the operating conditions of the above modes 1 to 4, if the state of charge SOC ≧ A, in the low load region of Pd ≦ P1, the mode 1 is selected in step S13 and the vehicle runs using only the motor generator 14 as a power source. And P1 <P
In the medium load region of d <P2, mode 2 is selected in step S17, and the vehicle travels using only the engine 12 as a power source.
In the high load region of ≤Pd, mode 4 is selected in step S19, and the vehicle travels using both the engine 12 and the motor generator 14 as power sources.

When SOC <A, the required output P
The power storage device 58 is charged by executing the mode 3 of step S14 in the middle and low load region where d is smaller than the second determination value P2. However, in the high load region where the required output Pd is equal to or more than the second determination value P2, in step S17. Mode 2 is selected, and high-power traveling is performed by the engine 12 without charging.

In the mode 2 of step S17, P1 <Pd
<P2 in the middle load range and SOC ≧ A, or P
This is executed in the high load region where d ≧ P2 and when SOC <A.
Since the energy efficiency of the engine 12 is superior to that of the engine 12, the fuel consumption and exhaust gas can be reduced as compared with the case where the vehicle runs using the motor generator 14 as a power source.

In a high load range, the vehicle travels in mode 4 in which the motor generator 14 and the engine 12 are used together.
However, when the state of charge SOC of the power storage device 58 is smaller than the minimum state of charge A, the operation in the mode 2 using only the engine 12 as a power source is performed, so that the state of charge SOC of the power storage device 58 is minimized. It is avoided that the charge amount becomes smaller than the storage amount A and the performance such as charge / discharge efficiency is impaired.

Next, the characteristic portion of the present embodiment to which the present invention is applied, that is, when the vehicle is stopped in the forward range, the vehicle moves backward (reverse).
The control operation for suitably preventing the reverse movement of the vehicle even when is not mechanically prohibited will be described based on the flowchart of FIG. In this control operation, step SA
Step 10 corresponds to the creep torque reducing means, and the step SA
Numeral 12 corresponds to the creep torque increasing means, and each corresponds to the creep torque changing means, and both are executed by the hybrid controller 50. The second speed stage (2nd) a series of signal processing is the vehicle backward by the automatic transmission control controller 52 to prevent reverse rotation of the output shaft 19 by accomplished by the action of the one-way clutch F ₂ a according to a command step SA9 It corresponds to prohibited means.

Referring to FIG. 8, at step SA1, the shift lever 42 allows the vehicle to travel forward.
For example, for "D", "4", "3", "2", and "L", whether or not any forward range other than "L" is selected is supplied from the shift position sensor 62. It is determined based on the signal. If this determination is affirmed, it is determined in step SA2 whether or not the mode 1 in which the vehicle runs using the motor generator 14 as a power source is selected based on the operation mode determination subroutine in FIG.

If this determination is affirmative, step S
In A3, foot brake or side brake is O
It is determined whether or not N is set. The foot brake is determined by turning on and off the brake switch 64, and the side brake is determined by turning on and off a parking brake switch (not shown).
If this determination is affirmed, it is determined in step SA4 whether or not the vehicle speed V is substantially 0 (vehicle stopped state) based on a signal supplied from the vehicle speed sensor 65.

If this determination is affirmative, step S
At A5, the accelerator operation amount θ _AC is substantially 0 (fully closed state) based on the signal supplied from the accelerator operation amount sensor 66.
Is determined. If any of the determinations at steps SA1 to SA5 is negative, at step SA6, the normal traveling control is executed according to the operation mode determination subroutine of FIG.

However, if the determination in step SA5 is affirmative, it is determined in step SA7 whether or not the oil temperature of the hydraulic circuit 40 is equal to or lower than _a predetermined value Ta based on a signal supplied from the oil temperature sensor 67. Is done. The predetermined value T _a has poor fluidity of the hydraulic fluid the oil temperature is an extremely low temperature, the shift in performing the clutch-to-clutch shifting from the second gear position (2nd) to third shift stage (3rd) This is a value that has been obtained in advance through experiments or the like, which may cause a shock.

If the determination in step SA7 is negative, the process proceeds to step SA8, where the second gear (2nd)
Of a control system provided in advance to achieve the above, or a control system provided in advance to smoothly execute a clutch-to-clutch shift from the second shift stage (2nd) to the third shift stage (3rd) It is determined whether or not it is impossible to establish the second shift speed due to a failure of a part of, for example, the 2-3 timing valve 89 and the linear solenoid valve SLU in FIG.

If this determination is denied, step S
At A9, a command for establishing the second shift stage is issued to the automatic transmission control controller 52, and excitation and non-excitation of the solenoid valves SL1 to SL4 are controlled in accordance with the instruction, whereby the hydraulic circuit 40 is switched. Thus, the second speed (2nd) is achieved. 2nd gear (2n
Since the reverse rotation of the output shaft 19 is prevented by d) the action of the one-way clutch F ₂ (hill hold function), the vehicle, such as during slope stop is prevented from being retracted. Next, in step SA10, the M / G controller 56 is controlled by the hybrid control controller 50, so that the current supplied to the motor generator 14 is reduced, the motor torque T _M is reduced, and the creep torque is reduced in step SA6. It is reduced or substantially zero compared to the case of the normal control.

Here, the second gear is more variable than the first gear.
Since the speed ratio is small, the motor torque T _MAre the same
Although the creep torque at the drive wheels is reduced,
Is the motor torque T_MWaste energy by reducing itself
It prevents Gyros.

When executing the above-described step SA10, the control is shifted to the normal control of step SA6 by turning off the brake, increasing the vehicle speed, etc., and when downshifting to the first gear and increasing the motor torque T _M , the creep torque is reduced. In order to prevent a shock or a sense of incongruity due to a sudden change, it is desirable to control the motor torque T _M so that the creep torque increases smoothly in consideration of the change in the gear ratio.

On the other hand, if any one of the determinations in steps SA7 and SA8 is affirmed, the automatic transmission control is executed in step SA11 because the second gear (2nd) cannot be achieved or it is not desirable to achieve it. A command to establish the first gear is issued to the controller 52, and the solenoid valves SL1 to SL
The hydraulic circuit 40 is controlled by controlling the excitation and non-excitation of the hydraulic circuit 40.
Is switched to achieve the first shift speed (1st).
Next, in the first gear (1st), the second gear (2nd)
Unlike the above, since the reverse rotation of the output shaft 19 is not mechanically prevented, the current supplied to the motor generator 14 is increased by controlling the M / G controller 56 by the hybrid control controller 50 in step SA12. The motor torque T _M is increased as compared with the case of step SA10. Motor torque T in this case
_M is set to substantially the same value as when a predetermined creep torque is generated when the accelerator is turned off in the normal control in step SA6, for example.

As described above, according to this embodiment, the vehicle stops.
Sometimes the second gear (2nd) is selected and the one-way clutch
F_TwoIf the vehicle is mechanically prohibited from retracting by
Is a step SA1 corresponding to the creep torque changing means.
0, the motor torque T _MIs lower than usual
Or approximately 0, the load on the motor generator 14 is reduced.
It is reduced and energy efficiency is improved. On the other hand, the first shift
Step (1st) is selected and retraction of the vehicle is mechanically prohibited.
If not, it is necessary to respond to the creep torque changing means.
In step SA12, the motor torque T_MIs above
Since it is increased more than in step SA10,
Backward movement (slipping) of the vehicle on the road is suitably prevented.

Although the embodiment of the present invention has been described in detail with reference to the drawings, the present invention can be applied to other embodiments.

For example, in the above-described embodiment,
Although the automatic transmission 18 having five gears and five forward gears has been used, as shown in FIG. 9, the automatic transmission 18 having only the main transmission 22 without the sub-transmission 20 is used. It is also possible to adopt the above, and to perform the shift control at four forward speeds and one reverse speed as shown in FIG.

In the above-described embodiment, the control for inhibiting the vehicle from retreating when the vehicle is stopped when the forward range is selected by the shift lever 42 has been described. However, the reverse range is selected by the shift lever 42. When the vehicle is stopped, the control may be such that the forward movement of the vehicle is prohibited.

In the case where the vehicle is mechanically prevented from retreating at the second speed (2nd), such as the automatic transmissions 18 and 60 of the present embodiment, for example, in the snow mode or the like,
It is also an embodiment of the present invention that the creep torque is reduced when the accelerator is turned off when starting second and when the accelerator is turned off when starting first in a normal mode.

In the above-described embodiment, the mode 1
Although the creep torque change control at the time of selection is described, the same control can be performed at the time of mode 5 selection. In this case, for example, when the forward range is selected, the second speed (2nd) is selected and the regenerative braking torque is controlled so as to reduce or substantially reduce the creep torque, thereby improving the fuel efficiency. When the second speed (2nd) cannot be selected, the vehicle is prevented from moving backward by controlling the regenerative braking torque so as to increase the creep torque.

Although not specifically exemplified, the present invention can be applied in various other modes without departing from the gist of the present invention.

[Brief description of the drawings]

FIG. 1 is a skeleton view illustrating a configuration of a hybrid drive device of a hybrid vehicle including a creep torque control device according to an embodiment of the present invention.

FIG. 2 is a diagram illustrating a control system provided in the hybrid drive device of FIG.

FIG. 3 is a diagram illustrating the operation of an engagement element that establishes each shift speed of the automatic transmission of FIG. 1;

FIG. 4 is a diagram showing a part of a hydraulic circuit of the automatic transmission of FIG. 1;

FIG. 5 is a diagram illustrating a connection relationship between the hybrid control controller of FIG. 2 and an electric torque converter.

FIG. 6 is a flowchart illustrating a basic operation of the hybrid drive device of FIG. 1;

FIG. 7 shows each mode 1 to 9 in the flowchart of FIG.
It is a figure explaining the operation state of.

FIG. 8 is a flowchart showing a main part of a control operation which is a feature of the present embodiment to which the present invention is applied.

FIG. 9 is a skeleton diagram showing a configuration of a hybrid drive device of a hybrid vehicle including an automatic transmission different from the embodiment of FIG. 1;

10 is a diagram illustrating the operation of an engagement element that establishes each shift speed of the automatic transmission in FIG. 9;

[Explanation of symbols]

12: Engine (power source) 14: Motor generator (power source) 24: Electric torque converter (power source) 50: Controller for hybrid control (creep torque control device) 52: Controller for automatic shift control (vehicle reverse prohibition means) F ₂ : one-way clutch (vehicle reverse prohibition means) Step SA9: vehicle reverse prohibition means Steps SA10 and SA12: creep torque changing means

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Yushi Hata 1 Toyota Town, Toyota City, Aichi Prefecture Inside Toyota Motor Corporation (72) Inventor Tsuyoshi Mika 1 Toyota Town, Toyota City, Aichi Prefecture Toyota Motor Corporation

Claims (2)

[Claims] In a driving range in which a driving force is generated by operating a power source in accordance with an accelerator operation amount, even when the accelerator operation amount is zero, the power source is operated to provide a predetermined creep torque to drive wheels. A vehicle reversal prohibition means for mechanically prohibiting reversal of the vehicle when the vehicle is stopped in the travel range, wherein the vehicle reversal prohibition means prohibits the vehicle from reversing. And a creep torque changing means for changing the creep torque depending on whether the creep torque is present or not. 2. The creep torque control device according to claim 1, wherein the power source is an electric motor.