JP2010235036A - Control device for automatic transmission - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a control device for automatic transmission, which can rapidly respond to an engine start request when it occurs during traveling of a vehicle, and hardly causes a shock according to the engine start. <P>SOLUTION: When the engine start request occurs during regenerative operation, a second brake B2 is released, and a motor generator MG is drive-controlled to normal rotation side, whereby the rotating speed of a third sun gear S3 in a second gear shift part 32 is reduced while maintaining the vehicle speed. Further, the engine 1 is started, whereby the rotating speed of a first ring gear R1 in a first gear shift part 31 is raised. Accordingly, the difference in rotating speed before and after a first clutch C1 is reduced, and when the difference in rotating speed is reduced to a predetermined value, engagement of the first clutch C1 is performed. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a control device for an automatic transmission mounted on a hybrid vehicle or the like having an engine (internal combustion engine) and a motor (electric motor) in a drive system. In particular, the present invention relates to improved control for starting an engine while the vehicle is running.

  In recent years, from the viewpoint of environmental protection and the like, reduction of exhaust gas emissions from engines mounted on vehicles and reduction of fuel consumption have been desired, and hybrid vehicles equipped with a hybrid system are vehicles that satisfy these requirements. It has been put into practical use (see, for example, Patent Document 1 and Patent Document 2 below).

  This hybrid vehicle includes a driving source (hereinafter referred to as an engine) such as a gasoline engine, and an electric motor (for example, a motor / generator or a motor: hereinafter referred to as a motor / generator) that generates electric power by the output of the engine or is driven by battery power. And one or both of the engine and the motor / generator is used as a travel drive source.

  In this type of hybrid vehicle, by controlling the driving and stopping of the engine and motor / generator based on various conditions, the engine / drive mode for driving only the engine and the motor / generator only are used to drive the motor / generator. The driving can be switched between a motor driving mode for driving as a motor and an engine / motor driving mode for driving both the engine and the motor / generator. Thereby, it is possible to reduce the exhaust gas emission amount, the fuel consumption amount, the noise, and the like. Further, by controlling the motor / generator to a power running state or a regenerative state, a positive torque can be applied to the output member, or a negative torque can be applied to the output member. For example, when the vehicle is coasting (coast traveling), a regenerative operation in which power is generated by a motor / generator using the rotational force of the drive wheels by applying a negative torque to the output member is possible.

JP 2005-162081 A JP 2006-118681 A

  By the way, in the hybrid vehicle as described above, in order to improve the efficiency during the regenerative operation (increase the power generation amount), it is effective to shut off the transmission including the motor / generator and the engine. That is, as disclosed in Patent Document 1, a clutch is provided on a power transmission path between a transmission (including a motor / generator) and an engine, and during regenerative operation, by releasing the clutch, It is intended to obtain a high regenerative efficiency by avoiding a decrease in the regenerative efficiency due to engine friction or the like.

  However, in the situation where the transmission and the engine are shut off as described above and the regenerative operation is performed, if a torque request is generated by the driver depressing the accelerator pedal, the clutch is engaged when the engine is started. Is required.

  Further, in a system that does not include an alternator as a power generation device for a vehicle and generates power by the motor / generator, for example, when the battery charge amount is insufficient during traveling in the motor drive mode, the clutch is also started when the engine is started. It is necessary to conclude.

  In order to respond quickly to such a request, it is desirable to start the engine and engage the clutch as soon as the above request (torque request or the like) occurs. However, in this case, since the engine is stopped before the above request occurs, a rotational difference is generated between the engine speed and the transmission speed. As a result, vibration on the vehicle deceleration side (also referred to as pulling shock) occurs, resulting in deterioration of drivability.

  As a technique for avoiding the pull-in shock, the engine is started with the clutch released, and after the start, the engine speed substantially coincides with the input shaft speed of the transmission (the engine side of the clutch). It is conceivable that the clutch is engaged at a timing when the rotational speed of the transmission and the rotational speed on the transmission side substantially coincide with each other.

  However, this requires waiting for the engine speed to increase to the input shaft speed of the transmission (waiting for the engine speed of the clutch to increase to the transmission speed). There will be a time lag between when a request (torque request, etc.) is generated and when the driving force of the engine is transmitted to the transmission or motor / generator, making it impossible to quickly respond to the request. . Further, in this case, the engine speed is controlled by the intake air amount. However, since the engine speed varies greatly with respect to the intake air amount, it is difficult to make the above-mentioned respective engine speeds coincide with each other.

  Further, in Patent Document 1, when the required driving force rapidly increases during electric travel using only the driving force of the motor, the engine clutch is slip-engaged to crank the engine, and the engine speed reaches a predetermined speed. When the engine clutch is released, the engine clutch is released and then the engine speed is higher than the transmission side rotation speed of the clutch. It is disclosed to ensure a large driving force to the wheels. However, in such an engine starting operation, a time required for slip-engaging the clutch, a time required for releasing the clutch thereafter, and a time required for slip-engaging the clutch again are required. It will take a long time before the torque is transmitted to the wheels, and the driver's request for driving force cannot be quickly met.

  Further, in Patent Document 2, a first clutch is provided between the engine and the motor / generator, and a second clutch is provided between the motor / generator and the wheel side. It is disclosed that when the motor side rotational speed is higher than a predetermined rotational speed, the second clutch is disengaged and the engine start standby state in which the first clutch is engaged is kept. As a result, when the engine is requested to start, cranking can be performed immediately. However, since the second clutch is released in the engine start standby state, the rotational force of the drive wheels is not transmitted to the motor / generator, and the regenerative operation cannot be performed.

  The present invention has been made in view of the above points, and an object of the present invention is to respond quickly to an engine start request when the vehicle is running and to accompany the engine start. It is an object of the present invention to provide a control device for an automatic transmission that hardly causes a shock.

-Principle of solving the problem-
The solution principle of the present invention devised to achieve the above object is that when the engine is started from the state where the vehicle is traveling with the rotation of the electric motor provided in the transmission unit, the transmission unit The brake means that has stopped the rotation of some of the rotating elements is released, whereby the engagement operation of the clutch that is engaged to transmit the driving force of the engine to the transmission unit and the change in the rotation speed of the motor are linked. The clutch can be engaged without any change in the vehicle speed due to the change in the rotational speed of the electric motor.

-Solution-
Specifically, according to the present invention, a clutch capable of interrupting the power transmission system path is disposed on the power transmission system path between the engine and the transmission unit, and the transmission unit includes the first rotation element, the first rotation element, and the like. The planetary gear device is provided with two rotation elements, a third rotation element, and a fourth rotation element. The first rotating element can transmit the driving force from the engine through the power transmission path when the clutch is engaged. The second rotation element is coupled to the output member of the transmission unit. The third rotation element can be stopped by the brake means. The fourth rotating element is connected to an electric motor and disposed integrally with the electric motor. Further, the gear selection means for selecting a gear speed based on the rotation speed of the second rotation element and the rotation of the third rotation element are stopped by the brake means, and the vehicle travels with the rotation of the electric motor. When starting the engine from this state, the engine is provided with engine start control means for releasing the brake means and allowing the rotation of the third rotating element.

  More specifically, when the brake means is released and the rotation speed of the second rotating element is made substantially constant, the speed stage selected by the speed stage selecting means is established and the engine side of the clutch is The number of revolutions of the first rotating element is adjusted by controlling the number of revolutions of the electric motor so as to synchronize the number of revolutions of the motor and the number of revolutions on the transmission unit side.

  Due to this specific matter, when the engine is started in the regenerative operation where the clutch is disengaged and the electric motor is driven to generate electric power (the vehicle is running with the rotation of the electric motor). The brake means is released to allow the third rotating element to rotate. This makes it possible to change the rotation speed of the other rotation elements while maintaining the rotation speed of the second rotation element among the rotation elements (the shift speed selected by the shift speed selection means is established). The rotational speed of the rotating element can be changed). In other words, the engine drive without causing a shock due to fluctuations in the rotation speed of the output member of the transmission (fluctuation in vehicle speed) due to changes in the rotation speeds of the first, third, and fourth rotation elements. The clutch can be engaged to transmit force to the transmission. For this reason, a large shock does not occur when the clutch is engaged due to a change in the rotational speed of these rotating elements. As a result, when an engine start request is generated while the vehicle is running, the request can be met promptly, and a shock associated with starting the engine hardly occurs.

  In addition, as described above, by controlling the rotational speed of the electric motor and adjusting the rotational speed of the first rotating element, the engine-side rotational speed and the transmission-side rotational speed of the clutch can be quickly synchronized. It is possible to shorten the period from when the engine start request is generated until the completion of engine start and the establishment of a power transmission path through which engine driving force is transmitted to the output member of the transmission unit. . Further, since there is no need to shut off the electric motor and the drive wheels, it is possible to continue the regenerative operation until the engine start is completed.

  Further, the planetary gear device is configured to amplify the driving torque of the motor input to the fourth rotating element and output the amplified torque from the second rotating element.

  Thereby, even if the drive torque of the electric motor is small, it is possible to give a sufficiently high torque to the output member of the transmission unit, and the electric motor can be downsized.

  Specific examples of the planetary gear device include the following two types. First, as a first type, the automatic transmission is provided with a first transmission unit and a second transmission unit. The first transmission unit includes a first sun gear, a pair of first pinions that mesh with each other, a first carrier that supports the first pinion so as to rotate and revolve, and a first gear that meshes with the first sun gear via the pair of first pinions. It consists of a double pinion type first planetary gear unit having a ring gear. The second transmission unit includes a second sun gear, a second pinion, a second carrier that supports the second pinion so as to rotate and revolve, and a single pinion type having a second ring gear that meshes with the second sun gear via the second pinion. A second sun gear, a third sun gear, a pair of third pinions that mesh with each other, a third carrier that supports the third pinion so as to rotate and revolve, and a third sun gear via the pair of third pinions. It consists of a double pinion type third planetary gear device having a meshing third ring gear. In the second transmission unit, the second carrier of the second planetary gear device and the third carrier of the third planetary gear device are integrated to form a common carrier. A ravinio type in which the second ring gear and the third ring gear of the third planetary gear device are integrated to form a common ring gear, and one of the second pinion and the pair of third pinions forms a common pinion. It is configured as a gear train. The first sun gear is always connected to a stationary member, the first carrier is connected to the engine so as to be able to transmit power, the first ring gear is decelerated with respect to the rotation of the first carrier, and is output. The second sun gear is selectively connected to the first carrier via a fourth clutch, is selectively connected to the first ring gear via a third clutch, and is a stationary member via a first brake. The third sun gear is selectively connected to the first ring gear via a first clutch, and the common carrier is connected to the engine via a second clutch so that power can be transmitted. The stationary ring is selectively connected to the stationary member via the second brake, and the common ring gear is connected to the output shaft. Further, the electric motor is connected to the second sun gear so that power can be transmitted. The first rotating element corresponds to the third sun gear, the second rotating element corresponds to the common ring gear, the third rotating element corresponds to the common carrier, and the fourth rotating element corresponds to the first sun gear. Corresponding to two sun gears, any one of the first to fourth clutches corresponds to the clutch, and the second brake corresponds to the brake means.

  As a second type, the automatic transmission is provided with a first transmission unit and a second transmission unit. The first transmission unit includes a first sun gear, a first pinion, a first carrier that supports the first pinion so as to rotate and revolve, and a single pinion type having a first ring gear that meshes with the first sun gear via the first pinion. The first planetary gear device. The second transmission unit includes a second sun gear, a second pinion, a second carrier that supports the second pinion so as to rotate and revolve, and a single pinion type having a second ring gear that meshes with the second sun gear via the second pinion. A second sun gear, a third sun gear, a pair of third pinions that mesh with each other, a third carrier that supports the third pinion so as to rotate and revolve, and a third sun gear via the pair of third pinions. It consists of a double pinion type third planetary gear device having a meshing third ring gear. In the second transmission unit, the second carrier of the second planetary gear device and the third carrier of the third planetary gear device are integrated to form a common carrier. A ravinio type in which the second ring gear and the third ring gear of the third planetary gear device are integrated to form a common ring gear, and one of the second pinion and the pair of third pinions forms a common pinion. It is configured as a gear train. The first sun gear is always connected to a stationary member, the first ring gear is connected to the engine so as to be able to transmit power, the first carrier is decelerated with respect to the rotation of the ring gear, and is output. The sun gear is selectively connected to the first carrier via a third clutch, and is selectively connected to a stationary member via a first brake. The third sun gear is connected to the first carrier via a first clutch. The common carrier is selectively connected to the carrier, and the common carrier is connected to the engine via a second clutch so as to transmit power, and is selectively connected to the stationary member via a second brake. The structure is connected to the output shaft. Further, the electric motor is connected to the second sun gear so that power can be transmitted. The first rotating element corresponds to the third sun gear, the second rotating element corresponds to the common ring gear, the third rotating element corresponds to the common carrier, and the fourth rotating element corresponds to the first sun gear. Corresponding to two sun gears, any one of the first to third clutches corresponds to the clutch, and the second brake corresponds to the brake means.

  In the present invention, the brake means that has stopped the rotation of some of the rotating elements in the transmission unit when the engine is started from the state where the vehicle is traveling with the rotation of the electric motor provided in the transmission unit. Thus, the clutch can be engaged without a change in the vehicle speed due to a change in the rotational speed of the rotation elements other than the rotation elements connected to the output member of the transmission unit. For this reason, when an engine start request is generated while the vehicle is running, it is possible to quickly respond to the request, and it is possible to hardly cause a shock accompanying the engine start.

1 is a schematic configuration diagram illustrating a power train of a vehicle according to an embodiment. It is a skeleton figure which shows the gear layout of the automatic transmission which concerns on embodiment. It is a figure which shows the engagement state for every gear stage of each clutch and each brake in a transmission mechanism part. It is a block diagram which shows the structure of a transmission control apparatus. It is a perspective view which shows a shift apparatus. It is a figure which shows the shift map used for the shift control of an automatic transmission. It is a collinear diagram which shows the rotation speed ratio of each rotation element in a 1st transmission part and a 2nd transmission part for every gear stage. It is a flowchart figure which shows the procedure of engine starting control. It is a collinear diagram which shows the rotation speed ratio of each rotation element at the time of engine starting control. It is a skeleton figure which shows the gear layout of the automatic transmission which concerns on a modification. It is a figure which shows the engagement state for every gear stage of each clutch and each brake in the transmission mechanism part which concerns on a modification.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the present embodiment, a case where the present invention is applied to an FR (front engine / rear drive) vehicle equipped with a hybrid system will be described.

  Before describing the engine start control which is a characteristic feature of the present embodiment, the vehicle power train, the basic operation of the automatic transmission, and the like will be described.

  FIG. 1 is a schematic configuration diagram showing a power train of a vehicle in the present embodiment, and FIG. 2 is a skeleton diagram showing an example of the automatic transmission 2 in FIG. In FIG. 2, only the upper half of the rotation center axis of the automatic transmission 2 is schematically shown.

  In FIG. 1, 1 is an engine, 2 is an automatic transmission, 3 is an engine control device (engine ECU), and 4 is a transmission control device (transmission ECU).

-Engine 1-
The engine 1 generates rotational power by burning an air-fuel mixture in which air sucked from outside and fuel injected from the fuel injection valve 5 are mixed at an appropriate ratio. The fuel injection valve 5 is controlled by the engine control device 3. In this embodiment, a gasoline engine is applied.

-Automatic transmission 2-
The automatic transmission 2 mainly includes a torque converter 20, a transmission mechanism 30, a hydraulic control device 40, and an oil pump 60, and can shift in eight forward speeds and two reverse speeds.

  As shown in FIG. 2, the torque converter 20 is connected to the output side of the engine 1, and includes a pump impeller 21, a turbine runner 22, a stator 23, a one-way clutch 24, a stator shaft 25, and a lock-up clutch 26. I have.

  The one-way clutch 24 supports the stator 23 on the case 2a of the automatic transmission 2 while allowing rotation in only one direction. The stator shaft 25 fixes the inner race of the one-way clutch 24 to the case 2a of the automatic transmission 2.

  The lock-up clutch 26 enables the pump impeller 21 of the torque converter 20 and the turbine runner 22 to be directly connected. If necessary, the lock-up clutch 26 directly engages the pump impeller 21 and the turbine runner 22, and the pump impeller. 21 is switched to a disengaged state in which the turbine runner 22 and the turbine runner 22 are separated from each other, and a half-engaged state intermediate between these engaged and disengaged states.

  The engagement force of the lockup clutch 26 is controlled by controlling the hydraulic pressure applied to the pump impeller 21 and the turbine runner 22 by the lockup control valve 27.

  The speed change mechanism portion 30 changes the rotational power input to the input shaft 9 from the torque converter 20 and outputs it to the output shaft 10. As shown in FIG. 2, the first speed change portion (front planetary) 31. And a second transmission unit (rear planetary) 32, an intermediate drum 33, first to fourth clutches C1 to C4, and first and second brakes B1 and B2.

  The first planetary gear unit 31A constituting the first transmission unit 31 is a gear type planetary mechanism called a double pinion type, and a pair of pinion gears (inner pinion gears P1a) meshing with each other with the first sun gear S1. And a first pinion P1 composed of an outer pinion gear P1b), a first carrier CA1 that supports the first pinion P1 so as to rotate and revolve, and a first ring gear that meshes with the first sun gear S1 via the first pinion P1. R1.

  The first sun gear S1 is fixed to the case 2a of the automatic transmission 2 so as not to rotate, and the first ring gear R1 can rotate integrally with the intermediate drum 33 via the third clutch C3 or can rotate relatively. The first sun gear S1 is concentrically inserted on the inner diameter side of the first ring gear R1. The first pinion P1 is interposed at a plurality of locations in the circumferential direction of the opposed annular space between the first sun gear S1 and the first ring gear R1, and the central axis of the first carrier CA1 is integrated with the input shaft 9. The support shaft portion that supports the first pinion P1 in the first carrier CA1 is supported by the intermediate drum 33 through the fourth clutch C4 so as to be integrally rotatable or relatively rotatable.

  The intermediate drum 33 is rotatably disposed on the outer peripheral side of the first ring gear R1, and is in a state in which it cannot rotate or is relatively rotatable with respect to the case 2a of the automatic transmission 2 via the first brake B1. It is supported.

  The second planetary gear device 32A and the third planetary gear device 32B constituting the second transmission unit 32 are gear type planetary mechanisms called a single pinion type and a double pinion type, respectively.

  The second planetary gear device 32A includes a second sun gear S2 having a relatively large diameter, a second pinion P2, a second carrier CA2 that supports the second pinion P2 so as to be capable of rotating and revolving, and a second pinion P2. And a second ring gear R2 meshing with the second sun gear S2.

  The third planetary gear unit 32B includes a third sun gear S3 having a relatively small diameter, a third pinion P3 including a pair of pinion gears (an inner pinion gear P3a and an outer pinion gear P3b) that mesh with each other, and the third pinion P3. And a third carrier CA3 that is supported so as to be able to revolve, and a third ring gear R3 that meshes with the third sun gear S3 via a third pinion P3.

  In the second transmission unit 32, the second carrier CA2 and the third carrier CA3 are integrated to constitute a common carrier CA that functions as a common member. Further, the second ring gear R2 and the third ring gear R3 are integrated to constitute a common ring gear R that functions as a common member. Thereby, this 2nd transmission part 32 is made into the gear type planetary mechanism (Ravinio type gear train) called the Ravinio type. In the second transmission unit 32, the second pinion P2 and the outer pinion gear P3b of the third pinion P3 are configured as a common pinion in the present invention, but the second pinion P2 and the third pinion P3 are used. The inner pinion gear P3a may be configured as a common pinion.

  The second sun gear S2 is connected to the intermediate drum 33, and the third sun gear S3 is connected to the first ring gear R1 of the first transmission unit 31 via the first clutch C1 so as to be integrally rotatable or relatively rotatable. The common ring gear R is integrally connected to the output shaft 10.

  The common carrier CA has a central shaft portion connected to the input shaft 9 via the second clutch C2, and each support shaft portion that supports the pinions P2, P3 (P3a, P3b) in the common carrier CA includes: It is supported by the case 2a of the automatic transmission 2 via the second brake B2.

  In the present embodiment, a motor / generator MG is incorporated in the second transmission unit 32. Specifically, the rotor MG-r of the motor / generator MG is connected to the intermediate drum 33 in the vicinity of the second sun gear S2 so as to rotate together. The stator MG-s of the motor / generator MG is fixed to the case 2a of the automatic transmission 2. For this reason, the rotor MG-r of the motor / generator MG is integrally rotated with the intermediate drum 33 and the second sun gear S2.

  The first to fourth clutches C1 to C4 and the first and second brakes B1 and B2 are configured as a wet multi-plate friction engagement device (friction engagement element) using the viscosity of oil.

  The 1st clutch C1 makes the 3rd sun gear S3 of the 2nd transmission part 32 into the engagement state which can rotate integrally with respect to 1st ring gear R1 of the 1st transmission part 31, or the release state which can be rotated relatively. .

  The second clutch C2 is configured to bring the common carrier CA of the second transmission unit 32 into an engaged state in which the common carrier CA can rotate integrally with the input shaft 9 or a released state in which relative rotation is possible.

  The third clutch C <b> 3 sets the first ring gear R <b> 1 of the first transmission unit 31 to an engaged state in which the first ring gear R <b> 1 can rotate integrally with the intermediate drum 33 or a released state in which relative rotation is possible.

  The fourth clutch C <b> 4 sets the first carrier CA <b> 1 of the first transmission unit 31 to an engaged state where the first carrier CA <b> 1 can rotate integrally with the intermediate drum 33 or a released state which allows relative rotation.

  The first brake B1 integrates the intermediate drum 33 with respect to the case 2a of the automatic transmission 2 so as to be in a non-rotatable engaged state or a rotatable disengaged state.

  The second brake B2 integrates the common carrier CA of the second transmission unit 32 with the case 2a of the automatic transmission 2 so as to be in a non-rotatable engaged state or a rotatable disengaged state.

  The second brake B2 is configured as a normally closed type friction engagement element. That is, when the hydraulic pressure is not supplied from the hydraulic control device 40, the common carrier CA of the second transmission unit 32 is integrated with the case 2a of the automatic transmission 2 so as not to rotate. On the other hand, when the hydraulic pressure is supplied from the hydraulic control device 40, the common carrier CA of the second transmission unit 32 is made free to be released.

  On the other hand, the first to fourth clutches C1 to C4 and the first brake B1, which are other friction engagement elements, are configured as normally open type friction engagement elements. That is, when the hydraulic pressure is not supplied from the hydraulic control device 40, the release state is established, whereas when the hydraulic pressure is supplied from the hydraulic control device 40, the engagement state is established.

  The hydraulic control device 40 controls the speed change operation of the speed change mechanism 30 and includes various linear solenoid valves, control valves, etc., and operates according to a control signal (control current) from the transmission control device 4, The clutches C1 to C4 and the brakes B1 and B2 can be switched between an engaged state and a released state.

  FIG. 3 is an engagement table showing the relationship between the engaged state or disengaged state in the first to fourth clutches C1 to C4 and the first and second brakes B1 and B2 and the respective shift speeds. In this engagement table, a circle indicates an “engaged state”, and a blank indicates a “released state”.

  Specifically, the first gear (1st) is established by engaging the first clutch C1 and the second brake B2, and the second speed is established by engaging the first clutch C1 and the first brake B1. When the gear stage (2nd) is established and the first clutch C1 and the third clutch C3 are engaged, the third speed gear stage (3rd) is established and the first clutch C1 and the fourth clutch C4 are engaged. Thus, the fourth gear stage (4th) is established. By engaging the first clutch C1 and the second clutch C2, the fifth gear stage (5th) is established, and the second clutch C2 and the fourth clutch C4 are engaged. By engaging, the 6th speed gear stage (6th) is established, and by engaging the 2nd clutch C2 and the 3rd clutch C3, the 7th speed gear stage (7th) is established, and the 2nd clutch C2 and the 2nd clutch Engaging one brake B1 Eighth gear (8th) is adapted to establish.

  The first reverse gear stage (Rev1) is established by engaging the third clutch C3 and the second brake B2, and the second reverse gear stage (Rev1) is established by engaging the fourth clutch C4 and the second brake B2. Rev2) is established. Further, by releasing all of the first clutch C1 to the fourth clutch C4 and the first and second brakes B1 and B2, the “N” range and the “P” range in which power transmission is interrupted are established. ing. In the “P” range, for example, the rotation of the output shaft 10 is mechanically fixed by a lock mechanism (not shown).

  In addition, the vehicle according to the present embodiment is configured to be able to run a motor using the motor / generator MG as a drive source. For example, when the vehicle starts or runs under a low load, the engine 1 is stopped and the motor / generator MG is stopped. Can be driven by. At this time, motor travel (ECO) is enabled by engaging the second brake B2. When the second brake B2 is engaged, the rotation of the common carrier CA is stopped, and the driving force of the motor / generator MG input from the second sun gear S2 is torque-amplified by the second transmission unit 32 to the common ring gear R. As a result, the motor can be driven by the motor / generator MG. As described above, when the motor travels, the driving torque of the motor / generator MG input to the second sun gear S2 is amplified and output to the common ring gear R. For this reason, even if the torque that can be output from the motor / generator MG is small, it can be used, and an increase in the size of the motor / generator MG can be suppressed.

  Further, when a driving force is input from the output shaft 10 side, such as during engine braking (coast running), regeneration control by the motor / generator MG is performed. Also at this time, the second brake B2 is engaged, and the rotation of the common carrier CA is stopped. Therefore, the motor / generator MG is driven to rotate (becomes driven) by the driving force input from the output shaft 10 side and is regenerated. At this time, the first clutch C1 to the fourth clutch C4 and the first brake B1 are automatically released as the hydraulic pressure is not supplied. Thereby, since the connection between the engine 1 and the output shaft 10 is cut off, the occurrence of regenerative loss due to the friction torque (frictional force) of the engine 1 is avoided. When the engine 1 is connected to the output shaft 10 (drive wheel) during regeneration, the friction torque of the engine 1 acts in a direction that cancels the driving force input from the output shaft 10 side, so the motor / generator MG. The regenerative amount will decrease.

-Engine control device 3, transmission control device 4-
The engine control device 3 and the transmission control device 4 are generally known ECUs (Electronic Control Units), and both have substantially the same hardware configuration. FIG. 4 shows a specific configuration of the transmission control device 4. The transmission control device 4 controls the hydraulic control device 40 to establish an appropriate shift stage, that is, a power transmission path in the transmission mechanism unit 30.

  That is, the transmission control device 4 includes a central processing unit (CPU) 51, a read only memory (ROM) 52, a random access memory (RAM) 53, a backup RAM 54, an input interface 55, as shown in FIG. The output interface 56 is connected to each other by a bidirectional bus 57.

  The CPU 51 executes arithmetic processing based on various control programs and control maps stored in the ROM 52. The ROM 52 stores various control programs for controlling the speed change operation of the speed change mechanism 30. The RAM 53 is a memory that temporarily stores calculation results in the CPU 51, data input from each sensor, and the like. The backup RAM 54 is a non-volatile memory that stores various data to be saved.

  The input interface 55 includes at least an engine speed sensor 91, an input shaft speed sensor 92, an output shaft speed sensor 93, a shift position sensor 94, an accelerator opening sensor 95, a G sensor 96, a vehicle speed sensor 97, a brake pedal sensor. 98, a brake master cylinder pressure sensor 99 and the like are connected. The output interface 56 is connected to at least the components of the hydraulic control device 40 (various linear solenoid valves and the like) and the lockup control valve 27 for controlling the hydraulic pressure of the lockup clutch 26.

  The engine rotation speed sensor 91 detects the rotation speed of the pump impeller 21 of the torque converter 20 to which the rotation of the engine 1 is transmitted as the engine rotation speed. The input shaft rotation speed sensor 92 detects the rotation speed (NT) of the input shaft 9. The output shaft rotational speed sensor 93 detects the rotational speed (NO) of the output shaft 10. The shift position sensor 94 detects an operation position of a shift lever described later. The accelerator opening sensor 95 detects the amount of depression of the accelerator pedal. The G sensor 96 detects the longitudinal acceleration of the vehicle. The vehicle speed sensor 97 detects the traveling speed of the vehicle. The brake pedal sensor 98 outputs a brake ON signal when the brake pedal is turned on (braking operation). The brake master cylinder pressure sensor 99 obtains the pedal depression amount when the brake pedal is turned on from the brake master cylinder pressure, thereby detecting the degree of braking demand of the driver.

  The transmission control device 4 is connected to the engine control device 3 so as to be able to transmit and receive, and acquires various information related to engine control from the engine control device 3 as necessary.

  Moreover, the shift apparatus 7 shown in FIG. 5 is arrange | positioned in the vicinity of the driver's seat of the vehicle which concerns on this embodiment. The shift device 71 is provided with a shift lever 71 so that it can be displaced. The shift device 7 has a parking (P) position, a reverse (R) position, a neutral (N) position, a drive (D) position, and a sequential (S) position. The shift lever 71 can be displaced to the position. The shift positions of these parking (P) position, reverse (R) position, neutral (N) position, drive (D) position, and sequential (S) position (including the “+” position and “−” position described below) are , Detected by the shift position sensor 94.

  Hereinafter, for each shift position (“N position”, “R position”, “D position”, “S position”) regarding the situation in which the shift position of the shift lever 71 is selected and the operation mode of the automatic transmission 2 at that time Explained.

  The “N position” is a position selected when the connection between the input shaft 9 and the output shaft 10 of the automatic transmission 2 is disconnected. When the shift lever 71 is operated to the “N position”, the automatic transmission All of the second clutches C1 to C4 and the brakes B1 and B2 are released (see FIG. 3).

  The “R position” is a position selected when the vehicle is moved backward, and when the shift lever 71 is operated to the R position, the automatic transmission 2 is switched to the reverse gear. As described above, when the vehicle is moving backward, the first reverse gear stage (Rev1) and the second reverse gear stage (Rev2) can be switched according to the vehicle speed or the like.

  The “D position” is a position selected when the vehicle moves forward. When the shift lever 71 is operated to this D position, a plurality of forward gears of the automatic transmission 2 are selected according to the driving state of the vehicle. The speed of the stage (eight speed forward) is automatically controlled.

  The “S position” is a position (manual shift position) that is selected when the driver manually performs a shift operation of a plurality of forward gears (eight forward speed), and the “−” position before and after the S position. And a “+” position is provided. The “+” position is a position where the shift lever 71 is operated during a manual upshift, and the “−” position is a position where the shift lever 71 is operated during a manual downshift. When the shift lever 71 is in the S position and the shift lever 71 is operated to the “+” position or the “−” position with the S position as the neutral position, the forward gear of the automatic transmission 2 is increased or decreased. Is done. Specifically, the gear stage is increased by one stage for each operation to the “+” position (for example, 1st → 2nd →... → 8th). On the other hand, the gear stage is lowered by one stage for each operation to the “−” position (for example, 8th → 5th →... → 1st).

-Shift control-
Next, a shift map used for shift control of the automatic transmission 2 configured as described above will be described with reference to FIG.

  The shift map shown in FIG. 6 is a map in which a vehicle speed and an accelerator opening are used as parameters, and a plurality of regions for obtaining an appropriate gear stage are set according to the vehicle speed and the accelerator opening, It is stored in the ROM 52 of the device 4. Each region of the shift map is partitioned by a plurality of shift lines (gear stage switching lines).

  In the shift map shown in FIG. 6, the upshift line (shift line) is indicated by a solid line, and the downshift line (shift line) is indicated by a broken line. Also, each switching direction of upshifting and downshifting is shown using numerals and arrows in the figure.

  Next, the basic operation of the shift control will be described.

  The transmission control device 4 calculates the vehicle speed from the output signal of the vehicle speed sensor 97, calculates the accelerator opening from the output signal of the accelerator opening sensor 95, and based on the vehicle speed and the accelerator opening, the shift map of FIG. The target gear stage is calculated with reference to the above, and the target gear stage is compared with the current gear stage to determine whether or not a speed change operation is necessary.

  According to the determination result, when there is no need for shifting (when the target gear stage and the current gear stage are the same and the gear stage is set appropriately), a solenoid control signal (hydraulic command Signal) to the hydraulic control device 40 of the automatic transmission 2.

  On the other hand, when the target gear stage and the current gear stage are different, shift control is performed. For example, when the driving state of the vehicle changes from the state where the gear stage of the automatic transmission 2 is running at the “5-speed” state, for example, the point A changes to the point B shown in FIG. Since the change occurs across the shift line [5 → 4], the target gear stage calculated from the shift map is “fourth speed”, and the solenoid control signal (hydraulic command signal) for setting the fourth gear stage is automatically shifted. Output to the hydraulic control device 40 of the machine 2 to perform a shift (5 → 4 downshift) from the fifth gear to the fourth gear.

  FIG. 7 is a collinear diagram (speed diagram) that can represent the rotational speeds of the rotating elements of the first transmission unit 31 and the second transmission unit 32 of the automatic transmission 2 by straight lines. In FIG. 7, the horizontal line X1 is the rotational speed “0”, X2 is the decelerated rotational speed output from the first ring gear R1, and X3 is the rotational speed “1.0”, that is, the same rotational speed as the input shaft 9. It is. Each vertical line of the first transmission unit 31 represents the first sun gear S1, the first ring gear R1, and the first carrier CA1 in order from the left side. The four vertical lines of the second transmission unit 32 indicate the common carrier CA, the second ring gear R2, and the third ring gear R3, which are composed of the second sun gear S2, the second carrier CA2, and the third carrier CA3 in order from the left side. The common ring gear R comprised by these and the 3rd sun gear S3 are represented.

  The third sun gear S3 in the second transmission unit 32 corresponds to the first rotating element (RE1) in the present invention, and the common ring gear R corresponds to the second rotating element (RE2) in the present invention. CA corresponds to the third rotating element (RE3) referred to in the present invention, and the second sun gear S2 corresponds to the fourth rotating element (RE4) referred to in the present invention.

  As shown in the nomograph, when the second brake B2 is engaged, the rotation of the common carrier CA is stopped, and when the first clutch C1 is engaged, the first sun gear S3 is engaged with the first sun gear S3. When the rotation of the first ring gear R1 decelerated by the transmission unit 31 with respect to the input shaft 9 is input, the common ring gear R connected to the output shaft 10 has a rotation speed indicated by the first speed gear stage “1st”. By rotating, the largest gear ratio (= the rotational speed of the input shaft 9 / the rotational speed of the output shaft 10) is obtained.

  When the rotation of the first ring gear R1 is input to the third sun gear S3 by engaging the first brake B1 and stopping the rotation of the second sun gear S2 and engaging the first clutch C1, The common ring gear R connected to the output shaft 10 is rotated at the rotational speed indicated by the second speed gear stage “2nd”, and a gear ratio smaller than that of the first speed gear stage “1st” is obtained. Here, when upshifting from the first gear to the second gear, the motor / generator MG is driven to the forward rotation side to quickly stop the rotation of the second sun gear S2, thereby changing the speed response. Will improve.

  The rotation of the first ring gear R1 is input to the third sun gear S3 by engaging the first clutch C1, and the rotation of the first ring gear R1 to the second sun gear S2 by engaging the third clutch C3. Is input, the common ring gear R connected to the output shaft 10 is rotated at the rotational speed indicated by the third speed gear stage “3rd”, and the transmission gear ratio is smaller than that of the second speed gear stage “2nd”. can get. Here, when upshifting from the second gear to the third gear, the motor / generator MG is driven to rotate forward so that the rotation speed of the second sun gear S2 is the rotation speed after the shift. The speed change response is improved by quickly raising the rotation speed to R1.

  When the first clutch C1 is engaged, the rotation of the first ring gear R1 is input to the third sun gear S3, and when the fourth clutch C4 is engaged, the rotation of the input shaft 9 is applied to the second sun gear S2. When input, the common ring gear R connected to the output shaft 10 is rotated at the rotational speed indicated by the fourth speed gear stage “4th”, and a gear ratio smaller than the third speed gear stage “3rd” is obtained. It is done. Here, when upshifting from the third speed gear stage to the fourth speed gear stage, the motor / generator MG is driven to rotate forward so that the rotational speed of the second sun gear S2 is the rotational speed after the shift. The speed change response is improved by quickly raising the rotation speed to

  When the first clutch C1 is engaged, the rotation of the first ring gear R1 is input to the third sun gear S3, and when the second clutch C2 is engaged, the rotation of the input shaft 9 is input to the common carrier CA. Then, the common ring gear R connected to the output shaft 10 is rotated at the rotational speed indicated by the fifth speed gear stage “5th”, and a gear ratio smaller than that of the fourth speed gear stage “4th” is obtained. . Here, when upshifting from the fourth gear to the fifth gear, the motor / generator MG is driven in the normal direction so that the rotational speed of the second sun gear S2 is increased to a predetermined rotational speed set after the shift. The speed change response is improved by raising the speed quickly.

  When the second clutch C2 is engaged, the rotation of the input shaft 9 is input to the common carrier CA, and when the fourth clutch C4 is engaged, the rotation of the input shaft 9 is input to the second sun gear S2. Then, the common ring gear R connected to the output shaft 10 is rotated at the rotational speed indicated by the sixth speed gear stage “6th”, and a gear ratio smaller than that of the fifth speed gear stage “5th” is obtained. Here, when upshifting from the fifth gear to the sixth gear, the motor / generator MG is driven reversely (or reversely braked / reversely regenerated), so that the rotational speed of the second sun gear S2 is changed after the shift. The speed change responsiveness is improved by quickly reducing the rotational speed of the input shaft 9 to the rotational speed.

  When the second clutch C2 is engaged, the rotation of the input shaft 9 is input to the common carrier CA, and when the third clutch C3 is engaged, the rotation speed of the first ring gear R1 is increased in the second sun gear S2. When input, the common ring gear R connected to the output shaft 10 is rotated at the rotational speed indicated by the seventh speed gear stage “7th”, and a gear ratio smaller than the sixth speed gear stage “6th” is obtained. It is done. Here, when upshifting from the sixth gear to the seventh gear, the motor / generator MG is driven reversely (or reversely braked / reversely regenerated), so that the rotational speed of the second sun gear S2 is changed after the shift. The speed change responsiveness is improved by quickly reducing the rotational speed to the rotational speed of the first ring gear R1.

  When the rotation of the input shaft 9 is input to the common carrier CA by the engagement of the second clutch C2, and the rotation of the second sun gear S2 is stopped by the engagement of the first brake B1, the output shaft The common ring gear R connected to the gear 10 is rotated at the rotational speed indicated by the eighth speed gear stage “8th”, and a gear ratio smaller than that of the seventh speed gear stage “7th” is obtained. Here, when upshifting from the seventh gear to the eighth gear, the motor / generator MG is driven in reverse rotation (or reverse braking / reverse rotation) to rotate the second sun gear S2 after shifting. By quickly reducing the speed to zero, the shift response is improved.

  When the third clutch C3 is engaged, the rotation of the first ring gear R1 is input to the second sun gear S2, and when the common carrier CA is stopped rotating by the engagement of the second brake B2. The common ring gear R2 connected to the output shaft 10 is rotated at the rotational speed indicated by the reverse first speed gear stage “Rev1”.

  When the rotation of the input shaft 9 is input to the second sun gear S2 by the engagement of the fourth clutch C4 and the rotation of the common carrier CA is stopped by the engagement of the second brake B2, the output shaft The common ring gear R connected to 10 is rotated at the rotational speed indicated by the reverse second speed gear stage “Rev2”.

  In the motor running by the motor / generator MG, when the common carrier CA is stopped from rotating by the engagement of the second brake B2, the common ring gear R connected to the output shaft 10 is "ECO" (FIG. 7), the motor / generator MG is rotated at a rotational speed reduced with respect to the rotational speed.

  Also, during regenerative operation, the same collinear chart as when the motor is driven by the motor / generator MG is shown, and the motor / generator MG is rotated by the driving force (rotational force of the driving wheels) input from the common ring gear R. Regeneration is carried out. At this time, since the motor / generator MG is increased in speed with respect to the rotation of the output shaft 10, the motor / generator MG can perform regenerative control at low torque and high rotation.

  Further, as described above, it is possible to improve the shift response by controlling the motor / generator MG when the automatic transmission 2 is upshifted, but it is preferable to control the motor / generator MG even when downshifting. By doing so, the shift response can be improved.

-Engine start control-
Next, engine start control during traveling of the vehicle, which is a characteristic operation of the automatic transmission 2 configured as described above, will be described. In the following description, the control when the engine start request is generated during coasting and when the driver depresses the accelerator during the regenerative operation will be described. As an example of the required gear stage (gear stage determined from the vehicle speed and the accelerator opening) when the engine start request is generated, the case of “second speed” will be described as a representative.

  First, an outline of engine start control in the present embodiment will be described. When an engine start request is generated during the regenerative operation in which the motor / generator MG generates power (the driven state of the motor / generator MG engaged with the second brake B2), the second brake B2 is released. Then, the motor generator MG is driven and controlled to the forward rotation side. As a result, the rotational speed of the third sun gear S3 in the second transmission unit 32 is decreased while maintaining the vehicle speed. That is, the rotational speed of the first clutch C1 on the second transmission unit 32 side is decreased. Simultaneously with this, or slightly prior to this, the engine 1 is started (cranking). Thereby, the rotation speed of the first ring gear R1 in the first transmission unit 31 is increased. That is, the rotational speed of the first clutch C1 on the first transmission unit 31 side (engine 1 side) is increased. In this way, the rotational speed difference between both sides of the first clutch C1 (the second transmission unit 32 side and the engine 1 side) is reduced, and when the rotational speed difference decreases to a predetermined value or less, the first The clutch C1 is engaged. When the target gear stage when the engine start request is generated is “second speed”, the first brake B1 is also engaged together with the engagement of the first clutch C1.

  Hereinafter, a specific operation of the engine start control according to the present embodiment will be described with reference to the flowchart of FIG. 8 and the alignment chart of FIG. The engine start control routine shown in FIG. 8 is executed in the transmission control device 4. Further, the routine shown in FIG. 8 is executed every predetermined time after the ignition switch is turned on, for example, every several milliseconds.

  First, in step ST1, it is determined whether or not the vehicle is currently traveling. This determination is made based on a vehicle speed detection signal from the vehicle speed sensor 97. If the vehicle is stopped, a NO determination is made in step ST1, and this routine is temporarily terminated.

  If the vehicle is running and the determination in step ST1 is YES, the process proceeds to step ST2 to determine whether the engine 1 is currently stopped. This determination is made based on the rotation speed signal from the engine rotation speed sensor 91. If the engine 1 is operating and the determination in step ST2 is NO, this routine is temporarily terminated.

  If the engine 1 is stopped and the determination in step ST2 is YES, the process proceeds to step ST3, where the regenerative operation is currently being performed, that is, the motor / generator MG is driven and power is generated. It is determined whether it is in a state. This determination is performed by detecting a control state with respect to the motor / generator MG and a storage state of a battery (not shown). That is, when the control state for the motor / generator MG is not the regenerative control state or when the battery is sufficiently charged, the regenerative operation is not performed, and therefore NO is determined in this step ST3. In this case, this routine is temporarily terminated.

  In the alignment chart shown in FIG. 9, the rotation state of each friction engagement element during the regenerative operation is indicated by a broken line. Specifically, since the engine 1 is stopped, the first sun gear S1, the first ring gear R1, and the first carrier CA1 in the first transmission unit 31 are all stopped. On the other hand, in the second transmission 32, the common carrier CA is stopped because the second brake B2 is engaged, and the common ring gear R is rotated at a speed corresponding to the vehicle speed because the vehicle is running. It is rotating. Accordingly, the second sun gear S2 and the third sun gear S3 are also rotating. In this case, on the alignment chart shown in FIG. 9, the third sun gear S3 is rotating forward, while the second sun gear S2 is rotating backward. As a result, the motor / generator MG that is rotationally integrated with the second sun gear S2 is also in a reversely driven state, thereby generating power by the motor / generator MG, that is, regenerative operation.

  If such regenerative operation is being performed and YES is determined in step ST3, the process proceeds to step ST4, where it is determined whether an engine start request has occurred. For example, when the driver depresses the accelerator, it is determined that an engine start request has occurred. This is determined based on an accelerator pedal depression amount signal from the accelerator opening sensor 95, for example. If no engine start request has been made and a negative determination is made in step ST4, this routine is temporarily terminated.

  On the other hand, if an engine start request is generated by the driver's accelerator depression operation or the like, a YES determination is made in step ST4, and the process proceeds to step ST5. In this step ST5, it is determined whether or not the gear stage (requested gear stage) at the time when the engine start request is generated is “2nd speed” or higher, that is, “2nd speed” to “8th speed”. As described above, the required gear stage is determined according to the shift map (FIG. 6) by detecting the vehicle speed and the accelerator opening (accelerator opening when the depression operation is performed). Shifting speed selection operation).

  If the requested gear is "2nd speed" or higher, a YES determination is made in step ST5, and the process proceeds to step ST6. In this step ST6, the engine start control is started and the release control of the second brake B2 is started.

  Specifically, in the engine start control, a starter motor (not shown) is started by a control signal from the engine control device 3 to start cranking of the engine 1 and fuel injection from the fuel injection valve 5 is performed. Then, the engine 1 is started. In addition, it recognizes from the engine speed etc. that the engine has started the combustion operation (one of the cylinders has reached the complete explosion state), and after the engine combustion operation has started, the energization to the starter motor is released. To do. With this engine start control, as indicated by the solid line on the first transmission unit 31 side in the collinear diagram of FIG. 9, the first carrier CA1 rotates and, accordingly, the first ring gear R1 also rotates in the same direction. Become. That is, the engine speed of the first clutch C1 increases.

  On the other hand, in the release control of the second brake B2, the oil pump 60 is driven to generate hydraulic pressure along with the cranking of the engine 1 by the engine start control, and the release operation of the second brake B2 is enabled. After only the hydraulic pressure is generated, the second brake B2 is released by the control signal from the transmission control device 4.

  The engine start control and the release control of the second brake B2 are started as described above, and the rotation control of the motor / generator MG is started in step ST7. In the rotation control of the motor / generator MG, the motor / generator MG is driven to the positive rotation side, that is, the motor / generator MG is energized to reduce the rotation speed of the second sun gear S2. I will let you. As the rotational speed of the motor / generator MG decreases, the rotational speed of the third sun gear S3 decreases (common ring gear R) as shown by the solid line on the second transmission unit 32 side in the alignment chart of FIG. The rotation speed (vehicle speed) does not change.) That is, the rotational speed of the first clutch C1 on the second transmission unit 32 side decreases (engine start operation by the engine start control means).

  While the engine start control described above increases the rotation speed of the first ring gear R1, that is, the engine-side rotation speed of the first clutch C1, the rotation control of the motor / generator MG controls the rotation speed of the third sun gear S3. The number of rotations on the second transmission unit 32 side in the one clutch C1 decreases (the number of synchronous rotations decreases). As a result, the difference between the rotation speed of the first clutch C1 on the first transmission section 31 side (engine 1 side) and the rotation speed on the second transmission section 32 side is rapidly reduced.

  In this manner, the engagement operation of the friction engagement element is started in step ST8 while controlling the rotation of the motor / generator MG. That is, when the required gear stage is “second speed”, both the first clutch C1 and the first brake B1 are engaged. In this case, as described above, there is almost no difference between the rotation speed on the first transmission section 31 side and the rotation speed on the second transmission section 32 side in the first clutch C1, so that the engagement of the first clutch C1 Shock is hardly generated, and a power transmission path is established in which the driving force of the engine 1 is transmitted to the output shaft 10 via the second transmission unit 32.

  When the required gear is 3rd to 8th, the clutch or brake that is engaged when the gear is established is engaged. As the rotation control of the motor / generator MG in this case, the rotation control of the motor / generator MG is performed so that the rotation speed of the second sun gear S2 can be obtained when it is assumed that the shift stage is established. For example, when the required gear stage is “3rd speed”, the rotation control of the motor / generator MG is performed so that the rotation speed of the second sun gear S2 matches the rotation speed of the first ring gear R1. That is, the motor / generator MG is controlled to rotate in the forward direction. When the requested gear stage is “fourth speed”, the rotation control of the motor / generator MG is performed so that the rotation speed of the second sun gear S2 matches the rotation speed of the first carrier CA1. That is, the motor / generator MG is controlled to rotate in the forward direction at a higher speed than in the case where the required gear stage is “third speed”.

  On the other hand, if the gear stage (requested gear stage) at the time when the engine start request is generated is “1st speed” and the determination in step ST5 is NO, the process proceeds to step ST9, where the friction engagement element is moved. The engine start control is started without performing an engagement operation or a release operation. That is, the cranking of the engine 1 is started while the second brake B2 is engaged, and the engine 1 is started by performing fuel injection from the fuel injection valve 5. Also in this case, it is recognized from the engine speed that the engine has started the combustion operation (one of the cylinders has reached the complete explosion state), and the starter motor is energized after the engine combustion operation has started. Will be canceled.

  In step ST10, the engagement operation of the first clutch C1 is started. As a result, the first clutch C1 and the first brake B1 are both engaged, and the first gear, which is the required gear stage, is established.

  When the requested gear stage at the time when the engine start request is generated is “1st speed” as described above, the driver's accelerator depressing operation amount is large, and the driver is requesting rapid acceleration. It is believed that there is. For this reason, even if a shock due to the engagement of the first clutch C1 occurs because the difference between the rotation speed on the first transmission section 31 side and the rotation speed on the second transmission section 32 side in the first clutch C1 is large, Don't be. In other words, the driver is in a situation where the shock is permitted and a rapid acceleration is requested. Therefore, when the requested gear stage is “1st speed”, the rotation control of the motor / generator MG described above or the like is performed. To meet this demand for rapid acceleration.

  As described above, in the present embodiment, the rotation speed of the second sun gear S2, the third sun gear S3, and the common carrier CA changes, so that the engine 1 does not generate a shock due to a change in vehicle speed. An engagement operation of a frictional engagement element (for example, the first clutch C1) can be performed to transmit the driving force to the second transmission unit 32. Further, by adjusting the rotational speed of the third sun gear S3 by controlling the rotational speed of the motor / generator MG, the rotational speed of the friction engagement element on the engine side and the rotational speed on the second transmission unit 32 side are quickly synchronized. It becomes possible. As a result, when an engine start request is generated while the vehicle is running, it is possible to respond quickly to the request, and it is possible to hardly cause a shock accompanying the engine start. Further, since there is no need to shut off the motor / generator MG and the drive wheels, it is possible to continue the regenerative operation until the engine start is completed.

(Modification)
Next, a modified example of the present invention will be described. In this modification, the gear layout of the automatic transmission is different from that of the above embodiment. Since other configurations and control operations are the same as those of the above-described embodiment, only differences from the above-described embodiment in the gear layout of the automatic transmission will be described here.

  FIG. 10 is a skeleton diagram showing a gear layout of the automatic transmission 2 according to this modification. Also in FIG. 10, only the upper half with respect to the rotation center axis of the automatic transmission 2 is schematically shown. In addition, the automatic transmission 2 according to this modification is capable of shifting in six forward speeds and one reverse speed.

  The first planetary gear unit 31A constituting the first transmission unit 31 in this modification is a geared planetary mechanism called a single pinion type, and includes a first sun gear S1, a first pinion P1, and a first pinion P1. A first carrier CA1 that supports the one pinion P1 so as to rotate and revolve, and a first ring gear R1 that meshes with the first sun gear S1 via the first pinion P1.

  The first sun gear S1 is fixed to the case 2a of the automatic transmission 2 and cannot rotate. The first ring gear R <b> 1 is connected to the input shaft 9 and is rotated integrally with the input shaft 9. The first ring gear R1 is supported by the common carrier CA of the second transmission unit 32 via the second clutch C2 so as to be integrally rotatable or relatively rotatable. The first carrier CA1 is supported by the intermediate drum 33 so as to be integrally rotatable, and can be integrally rotated or relatively rotated by the third sun gear S3 of the second transmission unit 32 via the first clutch C1. The second sun gear S2 of the second transmission unit 32 and the motor / generator MG are supported by the third clutch C3 so as to be integrally rotatable or relatively rotatable. The first pinion P1 is interposed at a plurality of locations in the circumferential direction of the opposed annular space between the first sun gear S1 and the first ring gear R1.

  The second transmission unit 32 has a second planetary gear unit 32A composed of a single-pinion type gear-type planetary mechanism and a third planetary gear unit 32B composed of a double-pinion-type gear-type planetary mechanism, as in the above embodiment. It has. Since the configuration of the planetary gear devices 32A and 32B is substantially the same as that of the above-described embodiment, description thereof is omitted here.

  FIG. 11 is an engagement table showing the relationship between the engaged state or disengaged state and the respective gear positions in the first to third clutches C1 to C3 and the first and second brakes B1 and B2. In this engagement table, a circle indicates an “engaged state”, and a blank indicates a “released state”.

  Specifically, the first gear (1st) is established by engaging the first clutch C1 and the second brake B2, and the second speed is established by engaging the first clutch C1 and the first brake B1. When the gear stage (2nd) is established and the first clutch C1 and the third clutch C3 are engaged, the third speed gear stage (3rd) is established and the first clutch C1 and the second clutch C2 are engaged. Thus, the fourth gear stage (4th) is established, and by engaging the second clutch C2 and the third clutch C3, the fifth gear stage (5th) is established, and the second clutch C2 and the first brake B1 are engaged. By engaging, the sixth speed gear stage (6th) is established.

  Further, the reverse gear stage (Rev) is established by engaging the third clutch C3 and the second brake B2. Further, by releasing all of the first clutch C1 to the third clutch C3 and the first and second brakes B1 and B2, the “N” range and the “P” range in which power transmission is interrupted are established. ing. In the “P” range, for example, the rotation of the output shaft 10 is mechanically fixed by a lock mechanism (not shown).

  In the vehicle according to the present embodiment, motor travel (ECO) and regenerative operation can be performed by engaging the second brake B2.

  The engine start control in this modification (control when an engine start request is generated during vehicle travel) is performed in the same manner as in the above-described embodiment. That is, when an engine start request is generated during the regenerative operation of the motor / generator MG, the second brake B2 is released and the motor / generator MG is driven and controlled to the forward rotation side. As a result, the rotational speed of the third sun gear S3 in the second transmission unit 32 is decreased while maintaining the vehicle speed. That is, the rotational speed of the first clutch C1 on the second transmission unit 32 side is decreased. In parallel with this, the engine 1 is started (cranking). Thereby, the rotation speed of the first ring gear R1 in the first transmission unit 31 is increased. That is, the rotational speed of the first clutch C1 on the first transmission unit 31 side (engine 1 side) is increased. In this way, the rotational speed difference between both sides of the first clutch C1 (the second transmission unit 32 side and the engine 1 side) is reduced, and when the rotational speed difference decreases to a predetermined value or less, the first The clutch C1 is engaged. When the target gear stage when the engine start request is generated is “second speed”, the first brake B1 is also engaged together with the engagement of the first clutch C1.

  Therefore, also in the present modification, as in the case of the above-described embodiment, when an engine start request is generated while the vehicle is running, the request can be met quickly and almost no shock is caused by the engine start. Can be.

-Other embodiments-
In the above-described embodiment, the case where the present invention is applied to the automatic transmission 2 capable of shifting to eight forward speeds and two reverse speeds will be described. In the above modification, the automatic transmission capable of shifting six forward speeds and one reverse speed is described. The case where the present invention is applied to the machine 2 has been described. The present invention is not limited to this, and can be applied to an automatic transmission having any other speed.

  In the above embodiment and the modification, the example in which the shift control is performed by obtaining an appropriate shift speed based on the vehicle speed and the accelerator opening is shown, but the present invention is not limited to this, and the vehicle speed and the throttle opening are not limited thereto. The shift control may be executed by obtaining an appropriate shift speed based on the degree.

  Further, the engine 1 mounted on the vehicle to which the present invention is applied is not limited to a gasoline engine but may be a diesel engine.

  Moreover, in the said embodiment and modification, control when an engine start request | requirement arose by the driver | operator's accelerator stepping operation being performed during regenerative driving etc. was demonstrated as engine start control. The present invention is not limited to this, and when an engine start request is generated due to a shortage of the battery storage amount during traveling in the motor drive mode in which the motor / generator MG is driven as an electric motor, the same engine start as described above is performed. Control may be performed.

  In the embodiment and the modification, the rotation control of the motor / generator MG is performed as the engine start control. However, the engine start control and the release control of the second brake B2 described above (step ST6 in the flowchart of FIG. 8). In the technical idea of the present invention, only the operation of the motor generator MG (the operation of step ST7 in the flowchart of FIG. 8) is performed.

  The present invention can be applied to engine start control when an engine start request is generated during vehicle travel in an automatic transmission mounted on a hybrid vehicle.

1 Engine 2 Automatic transmission 10 Output shaft (output member)
31 1st transmission part 31A 1st planetary gear apparatus 32 2nd transmission part (transmission part)
32A Second planetary gear unit 32B Third planetary gear unit S1 First sun gear S2 Second sun gear (fourth rotating element)
S3 Third sun gear (first rotating element)
P1 1st pinion P2 2nd pinion P3 3rd pinion R1 1st ring gear R2 2nd ring gear R3 3rd ring gear R Common ring gear (2nd rotation element)
CA1 First carrier CA2 Second carrier CA3 Third carrier CA Common carrier (third rotating element)
C1-C4 Clutch B1, B2 Brake (brake means)
MG motor generator (electric motor)

Claims (5)

On the power transmission system path between the engine and the transmission unit, a clutch that can shut off the power transmission system path is disposed. The transmission unit includes a first rotation element, a second rotation element, a third It is composed of a planetary gear device provided with a rotating element and a fourth rotating element,
The first rotating element is configured such that when the clutch is engaged, the driving force from the engine can be transmitted through the power transmission path.
The second rotating element is connected to an output member of the transmission unit,
The third rotation element can be stopped by the brake means,
The fourth rotating element is connected to an electric motor, and is disposed integrally with the electric motor,
Gear stage selecting means for selecting a gear stage based on the rotational speed of the second rotating element;
When the engine is started from a state where the rotation of the third rotating element is stopped by the brake means and the vehicle is running with the rotation of the electric motor, the brake means is released to rotate the third rotating element. A control device for an automatic transmission, characterized by comprising an allowed engine start control means. In the control device for an automatic transmission according to claim 1,
The engine start control means releases the brake means and establishes the speed stage selected by the speed stage selection means when the rotation speed of the second rotating element is substantially constant and the engine of the clutch. Control of the automatic transmission characterized in that the rotational speed of the electric motor is controlled so as to synchronize the rotational speed on the transmission side and the rotational speed on the transmission unit side to adjust the rotational speed of the first rotating element. apparatus. In the control device for an automatic transmission according to claim 1 or 2,
The control apparatus for an automatic transmission, wherein the planetary gear device is configured to amplify a driving torque of the motor input to the fourth rotating element and output the amplified torque from the second rotating element. In the control apparatus for an automatic transmission according to claim 1, 2, or 3,
The automatic transmission is
A double pinion type having a first sun gear, a pair of first pinions that mesh with each other, a first carrier that supports the first pinion so as to rotate and revolve, and a first ring gear that meshes with the first sun gear via the pair of first pinions. A first transmission unit comprising the first planetary gear device of
Single pinion type second planetary gear device having a second sun gear, a second pinion, a second carrier that supports the second pinion so as to rotate and revolve, and a second ring gear that meshes with the second sun gear via the second pinion. And a third sun gear, a pair of third pinions that mesh with each other, a third carrier that supports the third pinion so as to rotate and revolve, and a third ring gear that meshes with the third sun gear via the pair of third pinions. A second transmission unit comprising a double pinion type third planetary gear unit,
The second transmission unit is configured such that the second carrier of the second planetary gear device and the third carrier of the third planetary gear device are integrated to form a common carrier, and the second planetary gear device includes a second carrier. A ravinio gear train in which a ring gear and a third ring gear of the third planetary gear device are integrated to form a common ring gear, and one of the second pinion and the pair of third pinions forms a common pinion. Configured as
The first sun gear is always connected to a stationary member, the first carrier is connected to the engine so as to be able to transmit power, the first ring gear is decelerated and output with respect to the rotation of the first carrier,
The second sun gear is selectively connected to the first carrier via a fourth clutch, is selectively connected to the first ring gear via a third clutch, and is stationary via a first brake. The third sun gear is selectively connected to the first ring gear via a first clutch, and the common carrier is connected to the engine via a second clutch so that power can be transmitted. And the second brake is selectively connected to the stationary member, the common ring gear is connected to the output shaft,
The electric motor is coupled to the second sun gear so as to transmit power;
The first rotating element corresponds to the third sun gear, the second rotating element corresponds to the common ring gear, the third rotating element corresponds to the common carrier, and the fourth rotating element corresponds to the second sun gear. A control apparatus for an automatic transmission, wherein any one of the first to fourth clutches corresponds to the clutch, and the second brake corresponds to the brake means. In the control apparatus for an automatic transmission according to claim 1, 2, or 3,
The automatic transmission is
A first planetary gear device of a single pinion type having a first sun gear, a first pinion, a first carrier that supports the first pinion so as to rotate and revolve, and a first ring gear that meshes with the first sun gear via the first pinion. A first transmission unit comprising:
Single pinion type second planetary gear device having a second sun gear, a second pinion, a second carrier that supports the second pinion so as to rotate and revolve, and a second ring gear that meshes with the second sun gear via the second pinion. And a third sun gear, a pair of third pinions that mesh with each other, a third carrier that supports the third pinion so as to rotate and revolve, and a third ring gear that meshes with the third sun gear via the pair of third pinions. A second transmission unit comprising a double pinion type third planetary gear unit,
The second transmission unit is configured such that the second carrier of the second planetary gear device and the third carrier of the third planetary gear device are integrated to form a common carrier, and the second planetary gear device includes a second carrier. A ravinio gear train in which a ring gear and a third ring gear of the third planetary gear device are integrated to form a common ring gear, and one of the second pinion and the pair of third pinions forms a common pinion. Configured as
The first sun gear is always connected to a stationary member, the first ring gear is connected to the engine so as to be able to transmit power, the first carrier is decelerated with respect to the rotation of the ring gear, and is output.
The second sun gear is selectively connected to the first carrier via a third clutch and is selectively connected to a stationary member via a first brake, and the third sun gear is connected to the first clutch via a first clutch. The first carrier is selectively connected to the first carrier, the second carrier is connected to the engine via a second clutch so as to transmit power, and the second carrier is selectively connected to the stationary member via a second brake. The common ring gear is connected to the output shaft,
The electric motor is coupled to the second sun gear so as to transmit power;
The first rotating element corresponds to the third sun gear, the second rotating element corresponds to the common ring gear, the third rotating element corresponds to the common carrier, and the fourth rotating element corresponds to the second sun gear. A control apparatus for an automatic transmission, wherein any one of the first to third clutches corresponds to the clutch, and the second brake corresponds to the brake means.

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