JP6407780B2 - Vehicle drive device - Google Patents

Description

  The present invention relates to a vehicle drive device mounted on a vehicle, for example, and more specifically, a vehicle including an automatic transmission mechanism that enables inertial traveling by switching to a neutral state when a drive source is stopped while the vehicle is traveling. The present invention relates to a driving device.

  2. Description of the Related Art Conventionally, vehicle drive devices having an automatic transmission mechanism that can selectively form a plurality of shift stages by switching engagement and disengagement of a clutch and a brake have been widely used. In such a vehicle drive device, while the vehicle is running, all the clutches and brakes of the automatic transmission mechanism are released to switch to the neutral state, and coasting while the internal combustion engine is stopped improves fuel efficiency. A technique for achieving this is known (see Patent Document 1). In this vehicle drive device, the internal combustion engine restarts when the driver depresses the accelerator again during inertial traveling of the vehicle, and an appropriate shift stage is formed by engaging a predetermined clutch or brake. It returns to normal driving | running | working which drive | works with the driving force of.

  In such a vehicle drive device, since all the clutches and brakes are released during inertial running with the internal combustion engine stopped, two or more clutches or brakes are engaged to form one gear stage. When it is necessary to do this, a plurality of clutches or brakes must be engaged when returning from inertial running to normal running. For this reason, since a plurality of clutches or brakes must be engaged when the internal combustion engine is restarted, the response until the shift speed is formed and the driving force is generated is delayed.

  Here, as an automatic transmission mechanism, for example, one having an input side planetary gear and an output side planetary gear is widespread, and further has an input clutch for engaging and disengaging one rotation element of the output side planetary gear with the input shaft. Is popular. Therefore, it is conceivable that only the input clutch is engaged rather than releasing all the clutches and brakes during inertial running. As a result, it is possible to reduce the number of clutches or brakes to be engaged when returning to normal running, compared to the case where all clutches and brakes are released. It can suppress that the responsiveness of becomes slow.

JP 2006-160080 A

  However, in the vehicle drive device described in Patent Document 1, the neutral state is established by engaging the input clutch as described above during inertial running and releasing the clutch or brake that engages with the input clutch to form a shift stage. Then, in the output-side planetary gear in which one rotating element is connected to the output shaft, the rotating element connected to the output shaft rotates at a high speed as the vehicle coasts, whereas the rotating element connected to the input shaft Since the internal combustion engine is stopped along with the stop, other rotating elements may over-rotate (see, for example, FIG. 4B). In particular, when the vehicle is traveling at a high speed, there is a possibility that the vehicle may rotate at a higher speed than when the highest speed stage is formed, and suppression of such over-rotation has been desired. For example, even when a rotating electrical machine is mounted as a drive source, there is a possibility that over-rotation may occur during inertial running for the same reason as described above.

  Accordingly, an object of the present invention is to provide a vehicle drive device that can suppress over-rotation of a rotating element during inertial traveling while having an automatic transmission mechanism capable of inertial traveling in a neutral state with the drive source stopped.

A vehicle drive device according to the present disclosure is provided on an input member that is drivingly connected to a driving source, an output member that is drivingly connected to a wheel, and a power transmission path from the input member to the output member. A planetary gear set comprising a combination of planetary gears, having first, second, third and fourth rotating elements arranged in order corresponding to a gear ratio, wherein the third rotating element is drivingly connected to the output member; A plurality of engagement elements that can be engaged and disengaged by supply and discharge of hydraulic pressure, coupled to the first, second, and fourth rotation elements and capable of selectively forming a plurality of shift speeds by a combination of simultaneous engagement; An automatic transmission mechanism, a hydraulic control device capable of supplying and discharging hydraulic pressure to and from the engagement element, and a control device for electrically controlling the hydraulic control device, wherein the control device includes the drive source. Before stopping and coasting, Releases all of the engaging element coupled to the second rotating element or the fourth rotating element, wherein the drive source engages all of the engaging elements to rotate or stop the first rotary element after stopping.

  According to the vehicle drive device, when the inertial traveling is performed with the drive source stopped, all the engagement elements connected to the second rotation element or the fourth rotation element are released, and the first rotation element is rotated or Since at least some of the engaging elements to be stopped are engaged, the second rotating element and the fourth rotating element adjacent to the third rotating element coupled to the output member corresponding to the gear ratio are provided. Stopping and fixing is prevented. For this reason, since the output of any of the adjacent second rotating element and the fourth rotating element does not become 0 with respect to the third rotating element having a large output on the speed diagram, any one of the rotating elements is at the highest speed stage. Over-rotation beyond the range is suppressed. That is, it is possible to suppress over-rotation of the rotating element during inertial traveling while having an automatic transmission mechanism capable of inertial traveling in a neutral state with the drive source stopped.

The skeleton figure which shows the automatic transmission of 1st Embodiment. The engagement table | surface in the automatic transmission of 1st Embodiment. The speed diagram in the automatic transmission of 1st Embodiment. It is explanatory drawing which shows the case where only an input clutch is engaged during inertial running in an automatic transmission, (a) is an engagement table | surface, (b) is a speed diagram. In the automatic transmission of 1st Embodiment, it is explanatory drawing which shows the case where only the 1st brake is engaged during inertial running, (a) is an engagement table | surface, (b) is a speed diagram. In the automatic transmission of 1st Embodiment, it is explanatory drawing which shows the case where only the 1st brake and the 2nd brake are engaged during inertial running, (a) is an engagement table | surface, (b) is a speed diagram. The flowchart which shows the operation | movement at the time of the engine stop in driving | running | working in the automatic transmission of 1st Embodiment. The flowchart which shows the operation | movement at the time of engine starting in the inertial driving | running | working in the automatic transmission of 1st Embodiment. 4 is a time chart of engine rotation speed, hydraulic pressure supplied to each engagement element, and engine torque in the automatic transmission according to the first embodiment, where (a) is when the engine is stopped and (b) is when the engine is started. The skeleton figure which shows the automatic transmission of 2nd Embodiment. The engagement table | surface in the automatic transmission of 2nd Embodiment. The speed diagram in the automatic transmission of 2nd Embodiment. FIG. 6 is a time chart of engine rotation speed, hydraulic pressure supplied to each engagement element, and engine torque in the automatic transmission of the second embodiment, where (a) is when the engine is stopped and (b) is when the engine is started.

<First Embodiment>
Hereinafter, the control device 20 of the vehicle drive device 3 according to the first embodiment will be described with reference to FIGS. 1 to 3. In this specification, the drive connection refers to a state in which the rotating elements are connected so as to be able to transmit a driving force, and the rotating elements are connected so as to rotate integrally, or the rotating elements. Is used as a concept including a state in which driving force is transmitted through a clutch or the like.

  A schematic configuration of a vehicle 1 including the vehicle drive device 3 of the present embodiment will be described with reference to FIG. The vehicle 1 includes an internal combustion engine (drive source) 2, a vehicle drive device 3, wheels (not shown), and the like. The internal combustion engine 2 is an internal combustion engine such as a gasoline engine or a diesel engine, and is connected to the vehicle drive device 3. The vehicle drive device 3 includes an automatic transmission 10, an ECU (control device) 20, a hydraulic control device 30, a mechanical oil pump (MOP) 40, and an electric oil pump (original pressure generating unit, EOP) 50. And a mission case (case) 60.

  The automatic transmission 10 includes an input shaft 11 of the automatic transmission 10, a starting device 12, an input shaft (input member) 13 of a transmission mechanism (automatic transmission mechanism) 14, a transmission mechanism 14, and an output shaft (output member). 15 are arranged on the same axis. An input shaft 11 of the automatic transmission 10 is connected to the internal combustion engine 2.

  The starting device 12 includes a torque converter (fluid transmission device) 16 and a lock-up clutch 17 that can lock it up. The torque converter 16 is disposed between the pump impeller 16a connected to the input shaft 11 of the automatic transmission 10, the turbine runner 16b to which the rotation of the pump impeller 16a is transmitted via oil as a working fluid, and the like. And a stator 16c whose rotation is restricted in one direction by a one-way clutch 16d. The turbine runner 16 b is connected to the input shaft 13 of the transmission mechanism 14. The lock-up clutch 17 directly engages the front cover 17a and the input shaft 13 of the speed change mechanism 14 by engagement to bring the torque converter 16 into a locked-up state.

  The speed change mechanism 14 is accommodated in the case 60 and includes, in order from the input shaft 13 side, a first planetary gear (input planetary gear) SP1 and a planetary gear set PS composed of second and third planetary gears SP2 and SP3. The first to third planetary gears SP1 to SP3 are all configured by a single pinion planetary gear.

  The first planetary gear SP1 has a first sun gear S1, a first ring gear R1, and a first carrier CR1 that rotatably supports a first pinion P1 meshing with the first sun gear S1 and the first ring gear R1. Configured.

  The first sun gear S1 is always driven and connected to the input shaft 13 of the speed change mechanism 14. Further, the first ring gear R1 can be locked (fixed) to the case 60 by the first brake B1. The first carrier CR1 is drivingly connected to a second ring gear R2 of a second planetary gear SP2 described later, and can be locked (fixed) to the case 60 by a second brake B2.

  The planetary gear set PS is of a so-called Simpson type, and includes a second planetary gear SP2 and a third planetary gear SP3. The second planetary gear SP2 rotatably supports the second sun gear S2, the second ring gear R2 that is drivingly connected to the first carrier CR1, and the second pinion P2 that meshes with the second sun gear S2 and the second ring gear R2. And a second carrier CR2. In the second planetary gear SP2, the second ring gear R2 is the first rotating element of the planetary gear set PS, the second carrier CR2 is the second rotating element of the planetary gear set PS, and the second sun gear S2 is the fourth rotating element of the planetary gear set PS. Each corresponds (see FIG. 3).

  The third planetary gear SP3 meshes with the third sun gear S3 that is drivingly connected to the second sun gear S2, the third ring gear R3 that is drivingly connected to the second carrier CR2, and the third sun gear S3 and the third ring gear R3. And a third carrier CR3 that rotatably supports the third pinion P3. In the third planetary gear SP3, the third ring gear R3 is the second rotating element of the planetary gear set PS, the third carrier CR3 is the third rotating element of the planetary gear set PS, and the third sun gear S3 is the fourth rotating element of the planetary gear set PS. Each corresponds (see FIG. 3).

  The second sun gear S2 and the third sun gear S3 in the planetary gear set PS are connected to the first clutch C1 interposed between the input shaft 13 of the speed change mechanism 14, that is, the second sun gear S2 and the third sun gear S3. Is configured so that the rotation of the input shaft 13 can be selectively input via the first clutch C1.

  The second carrier CR2 and the third ring gear R3 in the planetary gear set PS are connected to the second clutch C2 interposed between the input shaft 13 of the speed change mechanism 14 and the rotation is locked to the case 60. It is connected to the obtained fourth brake B4 and connected to a one-way clutch F3 that restricts rotation in one direction with respect to the case 60. That is, the rotation of the input shaft 13 can be selectively inputted to the second carrier CR2 and the third ring gear R3 via the second clutch C2, and the rotation is caused to rotate in the direction of rotation from the internal combustion engine 2 by the one-way clutch F3. On the other hand, it is permitted and restricted with respect to the reverse rotation direction (engaged in the driving force output state), and the rotation can be locked by the fourth brake B4.

  The second ring gear R2 in the planetary gear set PS is connected to the second brake B2 capable of locking the rotation with respect to the case 60 via the first carrier CR1 described above, and the first ring gear R1 is connected to the case 60. The second ring gear R2 is decelerated from the first carrier CR1 by releasing the second brake B2 and being locked by the first brake B1. The rotation can be input, and the first brake B1 is released and the second brake B2 is locked, so that the rotation can be locked.

  The third carrier CR3 in the planetary gear set PS is connected to the output shaft 15, and is determined by the rotational states of the second sun gear S2, the third sun gear S3, the second carrier CR2, the third ring gear R3, and the second ring gear R2. Is output to a wheel (not shown) via the output shaft 15.

  Here, the second sun gear and the third sun gear in the planetary gear set PS are connected to the input shaft 13 via the first clutch C1, and the second carrier CR2 and the third ring gear R3 are connected to the input shaft via the second clutch C2. 13. Accordingly, the first clutch C1 and the second clutch C2 engage and disengage one rotation element of the planetary gear set PS with respect to the input shaft 13, and in the present embodiment, these are input clutches.

  That is, in the present embodiment, the speed change mechanism 14 is disposed on the input shaft 13 that is drivingly connected to the internal combustion engine 2, the output shaft 15 that is drivingly connected to the wheels, and the power transmission path from the input shaft 13 to the output shaft 15. A first planetary gear SP1 that is provided and connected to the input shaft 13 and a plurality of planetary gears SP2 and SP3, and includes first, second, third, and fourth rotating elements according to the arrangement order on the velocity diagram. A planetary gear set PS provided on the output shaft 15 side of the first planetary gear SP1 on the power transmission path, and a third carrier CR3, which is a third rotation element, drivingly connected to the output shaft 15, and a hydraulic pressure supply And a plurality of engagement elements C1, C2, B1, B2, and B4 that can selectively form a plurality of shift speeds by a combination of engaging and disengaging by exhaust and simultaneous engagement.

  The ECU 20 includes, for example, a CPU, a ROM that stores a processing program, a RAM that temporarily stores data, an input / output port, and a communication port, and controls the solenoid valves of the hydraulic control device 30. Various signals such as signals are output from the output port. The ECU 20 includes an accelerator opening sensor 71 that detects the accelerator opening, an input shaft rotation speed sensor 72 that detects the rotation speed of the input shaft 13, and an output shaft rotation speed sensor that detects the rotation speed of the output shaft 15. 73 is connected.

  The ECU 20 is configured to electrically control the hydraulic control device 30. The ECU 20 calculates the accelerator opening based on an output signal from the accelerator opening sensor 71 according to the amount of depression of the accelerator pedal by the driver. The ECU 20 calculates the vehicle speed based on the rotation speed obtained according to the output signal from the output shaft rotation speed sensor 73. Further, the ECU 20 determines whether the vehicle 1 is in a travel stop state or an acceleration request (start) by the driver based on the accelerator opening, the vehicle speed, the rotational speed of the input shaft 13 detected by the input shaft rotational speed sensor 72, and the like. Demand) is determined, and the gear position of the automatic transmission 10 is appropriately switched.

  The hydraulic control device 30 is configured by, for example, a valve body, generates line pressure or the like from the hydraulic pressure supplied from the mechanical oil pump 40 or the electric oil pump 50, and first and second based on a control signal from the ECU 20. The hydraulic pressure for controlling the two clutches C1, C2 and the first, second and fourth brakes B1, B2, B4 can be supplied and discharged.

  The mechanical oil pump 40 is, for example, drivingly connected to the pump impeller 16 a and is drivingly connected to the internal combustion engine 2 via the input shaft 11. The mechanical oil pump 40 and the internal combustion engine 2 can be appropriately connected by a combination of a sprocket and a chain, a gear train, or the like, and the rotational speed ratio is set by the structure of drive connection. The electric oil pump 50 is electrically driven independently of the mechanical oil pump 40 and is controlled by the ECU 20. The electric oil pump 50 generates and supplies an original pressure for generating a line pressure for engaging at least a part of the engaging elements when the internal combustion engine 2 is stopped.

  The vehicle drive device 3 configured as described above includes the first and second clutches C1, C2, the first, second, and fourth brakes B1, B2, B4, and the one-way clutch F3 shown in the skeleton of FIG. However, by operating in the combinations shown in the engagement table of FIG. 2, the first forward speed (1st) to the sixth forward speed (6th) and the reverse speed (Rev) are achieved according to the speed diagram of FIG. The

  Here, in the vehicle 1 described above, a case will be described in which the internal combustion engine 2 is stopped during traveling to perform a neutral traveling in a neutral state. In this case, for example, as shown in FIG. 4A, it is conceivable that only one of the first clutch C1 and the second clutch C2 that are input clutches is selected and engaged according to the vehicle speed. That is, at the time of high speed, only the second clutch C2 is engaged, and as the vehicle speed decreases, the clutch is switched from the second clutch C2 to the first clutch C1. However, in this case, as shown in FIG. 4B, when the second clutch C2 is engaged during high speed traveling, the third carrier CR3 connected to the output shaft 15 in the planetary gear set PS is at high speed. While the second clutch C2 connected to the input shaft 13 is stopped while rotating, the second and third sun gears S2 and S3 may over-rotate. That is, on the velocity diagram, there is a large difference in height between the third rotating element CR3 and the second rotating element R3, CR2 and the fourth rotating element S3, S2 adjacent to the third rotating element CR3. The speed line becomes steep, and any of the rotating elements may over-rotate beyond the sixth forward speed (highest speed).

  Therefore, in this embodiment, as shown in FIG. 5A, only the first brake B1 is engaged (the black circle is engaged in the figure). That is, the ECU 20 stops at least one of the engagement elements (first brake B1) that rotates the first rotation element R2 after the internal combustion engine 2 is started when the internal combustion engine 2 is stopped to perform the neutral running. A part of engagement elements (first brake B1) is engaged. In this case, as shown in FIG. 5 (b), the first ring gear R1 is rotationally fixed and the first sun gear S1 connected to the input shaft 13 is stopped. Therefore, the first carrier CR1 and the second ring gear are stopped. R2 also stops. As a result, the second and third sun gears S2 and S3 can be suppressed to a rotational speed equivalent to that at the sixth forward speed even when traveling at a high speed, so that the overspeed as shown in FIG. Can be suppressed. That is, it is possible to suppress the occurrence of a large difference in height between the third rotation element CR3 and the second rotation elements R3, CR2 and the fourth rotation elements S3, S2 adjacent to the third rotation element CR3 on the velocity diagram. It is possible to prevent the speed line between them from making a steep slope and to prevent any of the rotating elements from over-rotating beyond the highest speed stage.

  Further, in the present embodiment, only the first brake B1 is always engaged and held during inertial traveling, so there is no need to re-engage the clutch according to the vehicle speed as in the example shown in FIG. . For this reason, the engaging operation during inertia traveling is not required, and the fuel efficiency can be improved and the electric oil pump 50 can be downsized.

  Here, when the shift stage is formed after the internal combustion engine 2 is started after inertial running, the number of newly engaged engagement elements is smaller in terms of responsiveness than when all engagement elements are released. To preferred. In addition, when the internal combustion engine 2 is restarted, it is considered that the vehicle speed is often lower than when the inertial running is started. Therefore, when the internal combustion engine 2 is restarted, there is little need to form the highest speed stage. Conceivable. Furthermore, it is considered that there is little decelerating to a low speed such as the second forward speed in inertial traveling. Therefore, in the present embodiment, during inertial running, the first brake B1 for forming the fifth forward speed and the third forward speed is engaged after the internal combustion engine 2 is started, and the highest speed and the second forward speed are engaged. The second brake B2 for forming the step is released. Thus, while the fuel efficiency is improved, when forming the fifth forward speed or the third forward speed considered to be frequently selected, it is only necessary to engage one of the input clutches C1 and C2, and the forward 5 Responsiveness of returning to normal traveling when forming the first gear and the third forward gear can be improved.

  The ECU 20 selects any one of the fifth forward speed and the third forward speed that can be formed by using the engaged first brake B1 when the internal combustion engine 2 is requested to start during inertial running. The selected gear stage may be formed after the internal combustion engine 2 is started. That is, even when selecting the fourth forward speed or the highest speed in the determination based on the vehicle speed or the accelerator opening, priority is given to the responsiveness of returning to normal driving, and the fifth forward speed close to the original gear position or The third forward speed may be selected.

  Or as shown to Fig.5 (a), it is not restricted to engaging only 1st brake B1 during inertial running, You may make it engage only 2nd brake B2. In this case, the responsiveness of returning to the highest speed and the second forward speed can be improved.

  Alternatively, as shown in FIG. 6 (a), only the first brake B1 and the second brake B2 may be engaged during inertial running (black circles are engaged in the figure). That is, the ECU 20 engages all the remaining engagement elements (the first brake B1 and the second brake B2) when the internal combustion engine 2 is stopped and the inertial running is performed in the neutral state. In this case, as shown in FIG. 6B, since the first ring gear R1 and the first carrier CR1 are rotationally fixed, the second ring gear R2 is also rotationally fixed. As a result, the second and third sun gears S2 and S3 can be suppressed to a rotational speed equivalent to that at the sixth forward speed even when traveling at a high speed, so that the overspeed as shown in FIG. Can be suppressed.

  By the way, as described above, when the shift stage is formed after starting the internal combustion engine 2 after inertial running, it is preferable from the viewpoint of responsiveness that the number of newly engaged elements is small. Here, in the embodiment shown in FIG. 6, since the first brake B1 and the second brake B2 are engaged, the sixth forward speed, the fifth forward speed, the third forward speed, and the second forward speed are formed. In this case, one brake may be released and one input clutch C1, C2 may be engaged. Therefore, according to the present embodiment, it is possible to improve the responsiveness in returning to the normal traveling at the four shift speeds as compared with the case where all the engaging elements are released during the inertia traveling.

  In this case as well, when there is a request to start the internal combustion engine 2 during inertial running, the ECU 20 can be formed using the first brake B1 and the second brake B2 that are engaged, and the sixth forward speed and the fifth forward speed. Any one of the first speed, the third forward speed, and the second forward speed may be selected, and the selected shift speed may be formed after the internal combustion engine 2 is started. For this reason, since the second forward speed to the sixth forward speed other than the fourth forward speed can be selected, there are more options for the speed stage with improved responsiveness when returning to normal driving, and there are few options. Compared to this, drivability can be improved. In other words, by engaging and holding the engagement elements that do not affect the rotational speed of the planetary gear set PS, the number of shift stages that can be formed only by engagement of one engagement element is increased, and when returning to normal travel It is possible to realize drivability with little discomfort.

  Note that the ECU 20 already holds the second brake B2 when the internal combustion engine 2 is stopped and coasting is started during traveling at the highest speed stage (see FIG. 9A), for example. Since the ring gear R2 is rotationally fixed, the occurrence of excessive rotation as shown in FIG. 4B is suppressed. Therefore, the engagement of the first brake B1 may not be performed immediately after the internal combustion engine 2 is stopped, and the load of the electric oil pump 50 can be reduced by engaging the first brake B1 with a margin.

  As described above, in the present embodiment, as shown in FIGS. 5 and 6, the ECU 20 stops the internal combustion engine 2 and performs inertia traveling to perform the second rotation element R3, CR2 or the fourth rotation element S3. , S2 are released, and at least some of the engagement elements (first brake B1 and second brake B2) that release or engage or stop the first rotation element R2 are released. The engaging elements are engaged. Further, the ECU 20 engages at least a part of engagement elements (first brake B1 and second brake B2) that stop the first rotation element R2 when the internal combustion engine 2 is stopped and coasting is performed. Engage the elements.

Next, the operation of the vehicle drive device 3 will be described with reference to the flowcharts of FIGS. 7 and 8 and the time chart of FIG. Here, by satisfying a predetermined condition such as the accelerator opening being in an off state with a predetermined value or less during normal traveling at the highest speed stage, the internal combustion engine 2 is stopped and the speed change mechanism 14 is set in a neutral state to perform inertial traveling. In addition, the internal combustion engine 2 is restarted and an appropriate shift speed is set by the transmission mechanism 14 by satisfying a predetermined condition such as an accelerator opening being in an ON state of a predetermined value or more during inertial traveling. A description will be given of the operation when the vehicle is formed to return to normal running. In addition, here, a case where the first brake B1 and the second brake B2 are engaged and held during inertia running (FIG. 6) is described. In FIGS. 9A and 9B, N ₅ is the synchronous rotational speed at the fifth forward speed, and N ₆ is the synchronous rotational speed at the _sixth forward speed.

  First, it is assumed that the accelerator opening is in an ON state with a predetermined value or more, the lock-up clutch 17 is in an engaged state, the transmission mechanism 14 forms the highest speed stage, and the vehicle 1 normally travels at a high speed. . At this time, only the second clutch C2 and the second brake B2 are engaged (FIG. 9A). Further, the ECU 20 determines whether or not an engine stop command is turned on while the internal combustion engine 2 is being driven (step S1 in FIG. 7). The engine stop command here is assumed to be turned on, for example, when a condition such as the accelerator opening being equal to or less than a predetermined value is satisfied. If the ECU 20 determines that the engine stop command is not turned on, the process is terminated and the process is executed again from step S1.

  When the accelerator pedal is released by the driver and the accelerator opening is turned off to a predetermined value or less and other predetermined conditions are satisfied (t1 in FIG. 9A), the ECU 20 turns on the engine stop command. The internal combustion engine 2 is stopped (step S2 in FIG. 7). Then, the ECU 20 determines whether or not the lockup clutch 17 is in an engaged state (step S3 in FIG. 7). When the ECU 20 determines that the lockup clutch 17 is not engaged, the lockup clutch 17 is engaged (step S4 in FIG. 7). Thereby, when restarting the internal combustion engine 2, it is possible to prevent a delay in driving force transmission due to the torque converter 16.

  The ECU 20 determines whether or not the engine torque is less than 0 Nm (step S5 in FIG. 7). If the ECU 20 determines that the engine torque is not less than 0 Nm, the process is terminated and the process is executed again from step S1. When the ECU 20 determines that the engine torque is less than 0 Nm (t2 in FIG. 9A), the first clutch C1 or the second clutch C2 is released (step S6 in FIG. 7). In the present embodiment, since the highest speed stage is formed, since the second clutch C2 is engaged, only the second clutch C2 is released while the first clutch C1 is released. Further, for example, when the internal combustion engine 2 is stopped and coasting while the third forward speed is being established, the first clutch C1 is released. The reason why the first clutch C1 or the second clutch C2 is released when the engine torque is less than 0 Nm is that the clutches C1 and C2 can be smoothly released if the engine torque is less than 0 Nm, for example. The torque is not limited to 0 Nm as long as the torque enables the clutches C1 and C2 to be released.

  Subsequently, the ECU 20 puts the first brake B1 or the second brake B2 into a standby state (t3 in FIG. 9A, step S7 in FIG. 7). In the present embodiment, since the highest speed stage is formed, since the second brake B2 is engaged, only the first brake B1 is placed in a standby state. Further, the standby state here means that a hydraulic pressure lower than the engagement pressure is supplied to the engagement element, and for example, the distance between the friction plates is kept close until just before the engagement.

  The ECU 20 starts the electric oil pump 50 before the engine rotation speed becomes, for example, 500 rpm or less (step S8 in FIG. 7). As a result, even if the engine rotation speed becomes 500 rpm or less and it becomes difficult to generate the line pressure with the mechanical oil pump 40, the electric oil pump 50 supplies the original pressure for generating the line pressure instead. .

  Subsequently, the ECU 20 determines whether or not the engine speed is 0 rpm or less (step S9 in FIG. 7). If the ECU 20 determines that the engine speed is not 0 rpm or less, the process is terminated and the process is executed again from step S1. When the ECU 20 determines that the engine speed is 0 rpm or less (t4 in FIG. 9A), the first brake B1 or the second brake B2 is engaged and held (step S10 in FIG. 7). In the present embodiment, since the second brake B2 is already engaged, only the first brake B1 is engaged and held. Further, when the engine rotation speed is 0 rpm or less, the first brake B1 or the second brake B2 is engaged so that each brake B1, B2 can be smoothly engaged if the engine rotation speed is 0 rpm or less. This is because the rotational speed is such that the brakes B1 and B2 can be engaged. Since the ECU 20 already holds the second brake B2, the second ring gear R2 is rotationally fixed, so that the occurrence of overspeed as shown in FIG. 4B is suppressed. Therefore, the engagement of the first brake B1 may not be performed immediately after the internal combustion engine 2 is stopped, and the load of the electric oil pump 50 may be reduced by engaging the first brake B1 with a margin. .

  When the ECU 20 engages the first brake B1 and the second brake B2, the speed change mechanism 14 is engaged and disengaged as shown in the engagement table shown in FIG. 6A, and the speed diagram shown in FIG. It will start coasting in the state of. That is, all the engagement elements C1, C2, B4 connected to the second rotation element R3, CR2 or the fourth rotation element S3, S2 in the planetary gear set PS are released, and all the remaining engagement elements B1, B2 are released. It is designed to engage.

  Next, the internal combustion engine 2 is stopped, the accelerator opening is in an off state of a predetermined value or less, the lockup clutch 17 is in an engaged state, and the transmission mechanism 14 is engaged only with the first brake B1 and the second brake B2. In addition, it is assumed that the vehicle 1 is coasting in the neutral state (FIG. 9B). The ECU 20 determines whether or not the engine start command is turned on during coasting (step S11 in FIG. 8). The engine start command here is turned on, for example, when a condition such as the accelerator opening being equal to or greater than a predetermined value is satisfied. When the ECU 20 determines that the engine start command is not turned on, the process is terminated and the process is executed again from step S11.

  When the accelerator pedal is depressed by the driver and the accelerator opening is turned on to a predetermined value or more and other predetermined conditions are satisfied (t5 in FIG. 9B), the ECU 20 turns on the engine start command. The internal combustion engine 2 is started (step S12 in FIG. 8). The ECU 20 sets a gear stage suitable for the situation based on the vehicle speed and the accelerator opening at that time (step S13 in FIG. 8). Here, in the present embodiment, since the first brake B1 and the second brake B2 are engaged, the sixth forward speed that can be formed by using the first brake B1 and the second brake B2 that are engaged, It may be formed by selecting any one of the fifth speed, the third forward speed, and the second forward speed.

  After setting the gear position, the ECU 20 releases the first brake B1 or the second brake B2 in order to form the gear position (step S14 in FIG. 8). When forming the fourth forward speed, both the first brake B1 and the second brake B2 are released. Here, the fifth forward speed is formed, and the second brake B2 is released (t5 in FIG. 9B).

  The ECU 20 determines whether or not the rotational speed of the mechanical oil pump 40 exceeds the rotational speed at which line pressure can be generated, for example, 500 rpm (step S15 in FIG. 8). If the ECU 20 determines that the rotational speed of the mechanical oil pump 40 does not exceed the rotational speed at which the line pressure can be generated, the process is terminated and the process is executed again from step S11. When the ECU 20 determines that the rotational speed of the mechanical oil pump 40 exceeds the rotational speed at which the line pressure can be generated (t6 in FIG. 9B), the electric oil pump 50 is stopped (step S16 in FIG. 8). In addition, when the rotational speed of the mechanical oil pump 40 exceeds the rotational speed at which the line pressure can be generated, the electric oil pump 50 is stopped because the rotational speed of the mechanical oil pump 40 exceeds the rotational speed at which the line pressure can be generated. This is because the line pressure can be generated by the oil discharged from the mechanical oil pump 40, and the rotation speed at which such a line pressure can be generated is not limited to 500 rpm, and the idling of the internal combustion engine 2 is performed. The rotation speed can be set lower than the rotation speed.

  Subsequently, the ECU 20 places the first clutch C1 or the second clutch C2 in a standby state (step S17 in FIG. 8). When forming the fourth forward speed, both the first clutch C1 and the second clutch C2 are set in a standby state. Here, since the fifth forward speed is established, the second clutch C2 is set in a standby state.

  The ECU 20 calculates the absolute value of the synchronous differential rotation and determines whether or not the absolute value of the synchronous differential rotation is smaller than 50 rpm (step S18 in FIG. 8). Here, the synchronous differential rotation is a difference between the engine rotational speed and the synchronous rotational speed of the target shift stage. Further, in this determination, rotation synchronization is reliably determined for a predetermined time by setting an appropriate timer. When the ECU 20 determines that the absolute value of the synchronous differential rotation is not smaller than 50 rpm, the process is terminated and the process is executed again from step S11. When the ECU 20 determines that the absolute value of the synchronous differential rotation is smaller than 50 rpm (t7 in FIG. 9B), the first clutch C1 or the second clutch C2 is engaged and held (step S19 in FIG. 8). FIG. 9B, t8). When the fourth forward speed is established, both the first clutch C1 and the second clutch C2 are engaged and held. Here, since the fifth forward speed is formed, the second clutch C2 is engaged and held. Further, when the absolute value of the synchronous differential rotation is smaller than 50 rpm, the first clutch C1 or the second clutch C2 is engaged because the clutches C1 and C2 are smoothly engaged if the absolute value of the synchronous differential rotation is smaller than 50 rpm, for example. This is because it is possible to engage, and the rotation speed is such that the clutches C1 and C2 can be engaged.

  When the ECU 20 engages the first brake B1 and the second clutch C2, the speed change mechanism 14 is engaged and disengaged as shown in the engagement table shown in FIG. 2, and based on the speed diagram shown in FIG. It will come back to normal running with a speed.

  As described above, according to the vehicle drive device 3 of the present embodiment, when the internal combustion engine 2 is stopped and coasting is performed, the vehicle is connected to the second rotation element R3, CR2 or the fourth rotation element S3, S2. Engaging elements (first brake B1 and second brake B2) that release all engaging elements (first clutch C1, second clutch C2, fourth brake B4) and rotate or stop first rotating element R2. Since at least some of the engaging elements are engaged, the second rotating element R3, CR2 and the fourth rotating element S3, which are adjacent to the third rotating element CR3 connected to the output shaft 15 on the velocity diagram, are displayed. S2 is prevented from being stopped and fixed. For this reason, since the output of any of the adjacent second rotation element R3, CR2 and fourth rotation element S3, S2 does not become 0 with respect to the third rotation element CR3 that has a large output on the velocity diagram, either The over-rotation of the rotating element beyond the highest speed stage is suppressed. That is, it is possible to suppress the occurrence of a large difference in height between the third rotation element CR3 and the second rotation elements R3, CR2 and the fourth rotation elements S3, S2 adjacent to the third rotation element CR3 on the velocity diagram. It is possible to prevent the speed line between them from making a steep slope and to prevent any of the rotating elements from over-rotating beyond the highest speed stage. Accordingly, it is possible to suppress over-rotation of the rotating element during inertial traveling while having the speed change mechanism 14 capable of inertial traveling in the neutral state with the internal combustion engine 2 stopped.

  Further, according to the vehicle drive device 3 of the present embodiment, since at least one engagement element is engaged as compared with the case where all the engagement elements are released during inertial traveling, Responsiveness in return can be improved.

  Further, in the vehicle drive device 3 of the present embodiment, the ECU 20 stops the first rotation element R2 when the inertial running is performed with the internal combustion engine 2 stopped (the first brake B1 and the second brake). B2) is adapted to engage at least some of the engaging elements. For this reason, since the first rotation element R2 is fixedly stopped during inertial traveling, the second rotation element R3, CR2 or the fourth rotation element S3, S2 adjacent to the third rotation element CR3 is fixed. The overspeed of other rotating elements can be suppressed without making the gradient of the speed line steep.

  In the vehicle drive device 3 of the present embodiment shown in FIG. 5, the ECU 20 engages to rotate the first rotation element R <b> 2 after the internal combustion engine 2 is started when the internal combustion engine 2 is stopped and coasting is performed. The engagement element (first brake B1) of at least a part of the elements (first brake B1) is engaged. For this reason, since only the first brake B1 is always engaged and held during inertial traveling, there is no need to change the clutch according to the vehicle speed as in the example shown in FIG. Therefore, the fuel consumption can be improved and the electric oil pump 50 can be downsized. During inertial running, after the internal combustion engine 2 is started, the first brake B1 for forming the fifth forward speed and the third forward speed is engaged to form the highest speed stage and the second forward speed stage. The second brake B2 is released. Thus, while the fuel efficiency is improved, when forming the fifth forward speed or the third forward speed considered to be frequently selected, it is only necessary to engage one of the input clutches C1 and C2, and the forward 5 Responsiveness of returning to normal traveling when forming the first gear and the third forward gear can be improved.

  In the vehicle drive device 3 of the present embodiment shown in FIG. 6, when the ECU 20 stops the internal combustion engine 2 and performs inertial running, the remaining engagement elements (first brake) are stopped after the internal combustion engine 2 is stopped. B1 and the second brake B2) are all engaged. Therefore, when forming the sixth forward speed, the fifth forward speed, the third forward speed, and the second forward speed, it is only necessary to release one brake and engage one input clutch C1, C2. Compared with the case where all the engaging elements are released during traveling, the responsiveness in returning to normal traveling can be improved at the four shift speeds. Further, the ECU 20 can be configured to use the first brake B1 and the second brake B2 that are engaged when the internal combustion engine 2 is requested to start during inertia traveling, and can be formed using the sixth forward speed, the fifth forward speed, It is possible to select either the third forward speed or the second forward speed to form the selected gear stage after starting the internal combustion engine 2, and select the second forward speed to the sixth forward speed other than the fourth forward speed. As a result, the number of gear speed options with improved responsiveness when returning to normal driving is increased, and drivability can be improved compared to a case where there are few options. In other words, by engaging and holding the engagement elements that do not affect the rotational speed of the planetary gear set PS, the number of shift stages that can be formed only by engagement of one engagement element is increased, and when returning to normal travel It is possible to realize drivability with little discomfort.

  Further, in the vehicle drive device 3 of the present embodiment, the ECU 20 selects a gear stage that can be formed by using the engaging element that is engaged when there is a request to start the internal combustion engine 2 during inertial running. The selected gear stage may be formed after the internal combustion engine 2 is started. That is, even when the fourth forward speed is selected in the determination based on the vehicle speed or the accelerator opening, priority is given to the response to return to normal driving, and the fifth forward speed or the third forward speed close to the original gear position. Can be selected. Thereby, the responsiveness of the return to normal travel can be improved.

  Further, in the vehicle drive device 3 of the present embodiment, when the internal combustion engine 2 is stopped, the electric drive that generates a source pressure for engaging at least some of the engagement elements (the first brake B1 and the second brake B2). An oil pump 50 is provided. For this reason, even if the internal combustion engine 2 stops and the mechanical oil pump 40 stops, the engagement and holding of the first brake B1 and the second brake B2 can be realized.

<Second Embodiment>
Next, the vehicle drive device 3 according to the second embodiment will be described with reference to FIGS. 10 to 13. The vehicle drive device 3 of the present embodiment is different from the first embodiment in the speed change mechanism (automatic speed change mechanism) 114, and can form an eighth forward speed and a second reverse speed. Since other configurations are the same as those in the first embodiment, the same reference numerals are used and detailed description thereof is omitted.

  As shown in FIG. 10, the speed change mechanism 114 is housed in the case 60, and in order from the input shaft 13 side, the first planetary gear (input planetary gear) DP1, and the planetary gear set PS including the second and third planetary gears SP2 and DP3. It is equipped with. The first and third planetary gears SP1 and SP3 are both constituted by a double pinion planetary gear, and the second planetary gear SP2 is constituted by a single pinion planetary gear.

  The first planetary gear DP1 is a first carrier CR1 that rotatably supports a first sun gear S1, a first ring gear R1, and a first pinion P1 and a second pinion P2 meshing with the first sun gear S1 and the first ring gear R1. And is configured.

  The first sun gear S1 is fixed to the case 60. The first ring gear R1 is drivingly connected to the first clutch C1 and the third clutch C3. The first carrier CR1 is always drivingly connected to the input shaft 13 of the speed change mechanism 114 and is drivingly connected to the fourth clutch C4.

  The planetary gear set PS has a second planetary gear SP2 and a third planetary gear DP3. The second planetary gear SP2 includes a third sun gear S2 that is drivingly connected to the third clutch C3, the fourth clutch C4, and the first brake B1, and a third pinion P3 that meshes with the second sun gear S2 and a third ring gear R3 described later. And a second carrier CR2 that is rotatably supported. In the second planetary gear SP2, the second sun gear S2 corresponds to the first rotating element of the planetary gear set PS, and the second carrier CR2 corresponds to the second rotating element of the planetary gear set PS (see FIG. 12).

  The third planetary gear DP3 meshes with the third sun gear S3 that is drivingly connected to the first clutch C1, the third ring gear R3 that is drivingly connected to the output shaft 15, the third sun gear S3, and the third ring gear R3. And a third carrier CR3 that rotatably supports the fourth pinion P4 and the fifth pinion P5. In the third planetary gear DP3, the third carrier CR3 is the second rotating element of the planetary gear set PS, the third ring gear R3 is the third rotating element of the planetary gear set PS, and the third sun gear S3 is the fourth rotating element of the planetary gear set PS. Each corresponds (see FIG. 12).

  In the planetary gear set PS, the third pinion P3 and the fifth pinion P5 are configured by one long pinion. The second carrier CR2 and the third carrier CR3 in the planetary gear set PS are connected to the second clutch C2 interposed between the input shaft 13 of the speed change mechanism 114 and lock the rotation with respect to the case 60. It is connected to the obtained second brake B2 and connected to a one-way clutch F1 that restricts rotation in one direction with respect to the case 60. That is, the rotation of the input shaft 13 can be selectively input to the second carrier CR2 and the third carrier CR3 via the second clutch C2, and the rotation is caused to rotate in the direction of rotation from the internal combustion engine 2 by the one-way clutch F1. On the other hand, the rotation direction is restricted (engaged in the driving force output state) with respect to the reverse rotation direction, and the rotation can be locked by the second brake B2.

  The third ring gear R3 in the planetary gear set PS is connected to the output shaft 15, and the rotation determined by the rotation states of the second carrier CR2, the third carrier CR3, the second sun gear S2, and the third sun gear S3 is applied to the output shaft 15. To the wheel (not shown).

  Here, the third sun gear in the planetary gear set PS is connected via the first clutch C1 to the first ring gear R1 that is drivingly connected to the first carrier CR1 that is drivingly connected to the input shaft 13 at a predetermined reduction ratio. The second carrier CR2 and the third carrier CR3 are connected to the input shaft 13 via the second clutch C2. Accordingly, the first clutch C1 and the second clutch C2 engage and disengage one rotation element of the planetary gear set PS with respect to the input shaft 13, and in the present embodiment, these are input clutches.

  That is, in the present embodiment, the speed change mechanism 114 is on the input shaft 13 that is drivingly connected to the internal combustion engine 2, the output shaft 15 that is drivingly connected to the wheels, and the power transmission path from the input shaft 13 to the output shaft 15. A first planetary gear DP1 that is provided and connected to the input shaft 13 and a plurality of planetary gears SP2 and DP3 are combined, and the first, second, third, and fourth rotating elements are arranged in the order of arrangement on the velocity diagram. A planetary gear set PS provided on the output shaft 15 side of the first planetary gear DP1 on the power transmission path, and a third ring gear R3, which is a third rotation element, is drivingly connected to the output shaft 15; A plurality of engagement elements C1, C2, C3, C4, B1, and B2 that can selectively form a plurality of shift speeds by a combination that is engaged and disengaged by exhaust and simultaneously engaged.

  The vehicle drive device 3 configured as described above includes the first to fourth clutches C1 to C4, the first and second brakes B1 and B2, and the one-way clutch F1 shown in the skeleton of FIG. By operating in the combinations shown in the table, the first forward speed (1st) to the eighth forward speed (8th), the first reverse speed (Rev1) and the second reverse speed (Rev2) according to the speed diagram of FIG. Is achieved.

  In this embodiment, during inertial running, for example, only the first brake B1 is engaged. In this case, as shown in FIG. 12, the second sun gear S2 is stopped by the first brake B1. Thereby, even when the third sun gear S3 is traveling at a high speed, the third sun gear S3 can be suppressed to a rotational speed equivalent to that at the eighth forward speed, so that the excessive rotation as shown in FIG. 4B is suppressed. be able to. That is, on the velocity diagram, it is possible to suppress the occurrence of a large height difference between the third rotation element R3 and the second rotation elements CR3, CR2 and the fourth rotation element S3 adjacent to the third rotation element R3. The speed line between them does not become steep, and it is possible to suppress any of the rotating elements from over-rotating beyond the highest speed stage.

  Further, in the present embodiment, only the first brake B1 is always engaged and held during inertial traveling, so there is no need to re-engage the clutch according to the vehicle speed as in the example shown in FIG. . For this reason, the engaging operation during inertia traveling is not required, and the fuel efficiency can be improved and the electric oil pump 50 can be downsized.

  In this embodiment, during coasting, the first brake B1 for forming the eighth forward speed and the second forward speed is engaged after the internal combustion engine 2 is started, and the first speed for forming another gear stage is engaged. The third clutch C3 and the fourth clutch C4 are released. Thus, while improving fuel efficiency, it is only necessary to engage one of the input clutches C1 and C2 when forming the eighth forward speed or the second forward speed. Responsiveness of returning to normal running when forming can be improved.

  The ECU 20 selects any one of the eighth forward speed and the second forward speed that can be formed by using the engaged first brake B1 when the internal combustion engine 2 is requested to start during inertial running. The selected gear stage may be formed after the internal combustion engine 2 is started. In other words, even when another shift speed is selected in the determination based on the vehicle speed or the accelerator opening, priority is given to the responsiveness of returning to normal driving, and the forward 8th speed or the 2nd forward speed close to the original speed. May be selected.

  Or it is not restricted to engaging only the 1st brake B1 during inertial running, You may make it engage only the 3rd clutch C3 or the 4th clutch C4. Alternatively, the third clutch C3 or the fourth clutch C4 may be engaged in addition to the first brake B1. In these cases, it is possible to improve the responsiveness of returning to the shift stage that can be formed together with the input clutches C1 and C2.

  Alternatively, it is not limited to engaging only one engaging element during inertial traveling, and all the third and fourth clutches C3 and C4 and the first brake B1 may be engaged during inertial traveling. Good. That is, the ECU 20 engages all the remaining engagement elements (the third and fourth clutches C3 and C4 and the first brake B1) when the internal combustion engine 2 is stopped and coasting is performed. In this case, the second sun gear S2 is rotationally fixed by the first brake B1. Thereby, even when the third sun gear S3 is traveling at a high speed, the third sun gear S3 can be suppressed to a rotational speed equivalent to that at the eighth forward speed, so that the excessive rotation as shown in FIG. 4B is suppressed. be able to.

  In this case, since the third and fourth clutches C3 and C4 and the first brake B1 are engaged, the eighth forward speed, the seventh forward speed, the sixth forward speed, the fourth forward speed, and the third forward speed. When forming the second speed and the second forward speed, it is only necessary to release the two engaging elements and engage one of the input clutches C1 and C2. Therefore, according to the present embodiment, it is possible to improve the responsiveness in returning to the normal traveling at the six shift speeds as compared with the case where all the engaging elements are released during the inertia traveling.

  Also in this case, the ECU 20 is capable of being formed using the first brake B1 and the second brake B2 that are engaged when there is a request to start the internal combustion engine 2 during inertial traveling, and the forward seventh speed and the seventh forward speed. It is also possible to select any one of the first speed, the sixth forward speed, the fourth forward speed, the third forward speed, and the second forward speed to form the selected shift speed after the internal combustion engine 2 is started. For this reason, since the second forward speed to the eighth forward speed other than the fifth forward speed can be selected, the number of options for the speed stage with improved responsiveness when returning to normal driving increases, and the number of options is small. Compared to this, drivability can be improved.

  For example, when the internal combustion engine 2 is stopped and the inertial running is started during traveling at the highest speed stage, the ECU 20 already holds the first brake B1 (see FIG. 13A). Since the sun gear S2 is rotationally fixed, the occurrence of excessive rotation as shown in FIG. 4B is suppressed. Therefore, the engagement of the third and fourth clutches C3 and C4 may not be performed immediately after the internal combustion engine 2 is stopped, and the electric oil pump is engaged by engaging the third and fourth clutches C3 and C4 with a margin. 50 loads can be reduced.

  As described above, in the present embodiment, the ECU 20 stops all the engagement elements C1 connected to the second rotation elements CR3 and CR2 or the fourth rotation element S3 when the internal combustion engine 2 is stopped and coasting is performed. , C2, B2 are released, and at least some of the remaining engaging elements (the third and fourth clutches C3, C4 and the first brake B1) are engaged. Further, the ECU 20 stops at least one of the engagement elements (the third and fourth clutches C3 and C4 and the first brake B1) that stops the first rotation element S2 when the internal combustion engine 2 is stopped and coasting is performed. A part of the engaging elements are engaged.

Next, operation | movement of the vehicle drive device 3 of this embodiment is demonstrated along the time chart of FIG. Here, the internal combustion engine 2 is stopped and the speed change mechanism 114 is operated by satisfying a predetermined condition such as an accelerator opening being in an off state of a predetermined value or less during normal traveling at the eighth forward speed (highest speed). The operation in the case of coasting in the neutral state will be described, and the internal combustion engine 2 is restarted and the speed change mechanism by satisfying predetermined conditions such as the accelerator opening being in an ON state greater than a predetermined value during coasting. The operation when an appropriate shift stage is formed by 114 and the vehicle returns to normal travel will be described. Here, the case where the third and fourth clutches C3 and C4 and the first brake B1 are engaged and held during inertial traveling is described. 13 (a) and 13 (b), N ₆ is the synchronous rotational speed at the sixth forward speed, N ₇ is the synchronous rotational speed at the _seventh forward speed, and N ₈ is the eighth forward speed. Synchronous rotation speed.

  First, as shown in FIG. 13 (a), the accelerator opening is in an ON state with a predetermined value or more, the lockup clutch 17 is in an engaged state, the transmission mechanism 114 forms the highest speed stage, and the vehicle 1 is It is assumed that the vehicle is traveling normally at high speed. At this time, only the second clutch C2 and the first brake B1 are engaged.

  When the accelerator pedal is released by the driver and the accelerator opening is turned off to a predetermined value or less and other predetermined conditions are satisfied (t11), the ECU 20 determines that the engine stop command is turned on, and the internal combustion engine 2 is stopped.

  When the ECU 20 determines that the engine torque is less than 0 Nm (t12), the second clutch C2 is released. Subsequently, the ECU 20 places the third and fourth clutches C3 and C4 in a standby state (t13). Here, the third and fourth clutches C3 and C4 are sequentially executed one by one without being put into a standby state at the same time. Thereby, it can suppress that required hydraulic pressure becomes excessive.

  Subsequently, when the ECU 20 determines that the engine rotation speed is 0 rpm or less (t14), the ECU 20 engages and holds the third and fourth clutches C3 and C4. When the ECU 20 engages the first brake B1 and the third and fourth clutches C3 and C4, the speed change mechanism 114 is coasted in a neutral state. That is, all the engagement elements C1, C2, B2 connected to the second rotation element CR3, CR2 or the fourth rotation element S3 in the planetary gear set PS are released, and all the remaining engagement elements C3, C4, B1 are released. It is designed to engage.

  Next, as shown in FIG. 13 (b), the internal combustion engine 2 is stopped, the accelerator opening is in an off state equal to or less than a predetermined value, the lockup clutch 17 is in an engaged state, and the transmission mechanism 114 has a third state. The fourth clutch C3, C4 and the first brake B1 are engaged, and the vehicle 1 is coasting in the neutral state.

  When the accelerator pedal is depressed by the driver and the accelerator opening is turned on at a predetermined value or more and other predetermined conditions are satisfied (t15), the ECU 20 determines that the engine start command is turned on, and the internal combustion engine Start 2 The ECU 20 sets a gear position suitable for the situation based on the vehicle speed and the accelerator opening at that time. In this embodiment, since the third and fourth clutches C3 and C4 and the first brake B1 are engaged, the third and fourth clutches C3 and C4 and the first brake B1 that are engaged are used. It may be formed by selecting any one of the eighth forward speed, the seventh forward speed, the sixth forward speed, the fourth forward speed, the third forward speed, and the second forward speed.

  After setting the gear position, the ECU 20 releases the two engaging elements from the third and fourth clutches C3 and C4 and the first brake B1 in order to form the gear position. Here, the sixth forward speed is formed, and the third clutch C3 and the first brake B1 are released (t15).

  When the ECU 20 determines that the engine speed has exceeded 500 rpm (t16), the electric oil pump 50 is stopped. Subsequently, the ECU 20 puts the second clutch C2 into a standby state in order to form the sixth forward speed. When the ECU 20 determines that the absolute value of the synchronous differential rotation is smaller than 50 rpm (t17), the ECU 20 engages and holds the second clutch C2 (t18).

  When the ECU 20 engages the second clutch C2 and the fourth clutch C4, the speed change mechanism 114 is engaged and disengaged as shown in the engagement table shown in FIG. 11, and based on the speed diagram shown in FIG. It will come back to normal running with a speed.

  As described above, according to the vehicle drive device 3 of the present embodiment, when the internal combustion engine 2 is stopped and the inertial running is performed, all connected to the second rotating element CR3, CR2 or the fourth rotating element S3. The engaging elements (first clutch C1, second clutch C2, second brake B2) are released, and at least one of the remaining engaging elements (third, fourth clutches C3, C4 and first brake B1) is released. The second rotating elements CR3 and CR2 and the fourth rotating element S3 adjacent to each other on the speed diagram to the third rotating element R3 connected to the output shaft 15 are stopped and fixed. Is prevented. For this reason, the output of any of the adjacent second rotation elements CR3 and CR2 and the fourth rotation element S3 does not become 0 with respect to the third rotation element R3 that has a large output on the velocity diagram. The element is prevented from over-rotating beyond the highest speed stage. Therefore, it is possible to suppress over-rotation of the rotating element during inertial traveling while having the speed change mechanism 114 capable of inertial traveling in the neutral state with the internal combustion engine 2 stopped.

  In the first and second embodiments described above, the case where the vehicle drive device 3 includes the automatic transmission 10 has been described. However, the present invention is not limited to this. For example, the vehicle drive device 3 may include a first electric motor MG1, a second electric motor MG2, and a power distribution mechanism, and may be applied to a so-called split hybrid vehicle. In this case, overspeed of the planetary gear set PS can be suppressed, and the engagement element that does not affect the rotation speed of the planetary gear set PS is engaged and held, so that a shift that can be formed only by engagement of one engagement element. By increasing the number of steps, it is possible to realize drivability and early regeneration with little discomfort when returning to normal driving.

  In addition, 1st and 2nd embodiment is provided with the following structures at least. The vehicle drive device (3) of the first and second embodiments includes an input member (13) drivingly connected to a driving source (2), an output member (15) drivingly connected to a wheel, and the input It is provided on the power transmission path from the member (13) to the output member (15), and consists of a combination of a plurality of planetary gears (SP1, SP2, SP3, DP1, SP2, DP3), and in order corresponding to the gear ratio. A planetary gear set (PS) having first, second, third, and fourth rotating elements arranged side by side, wherein the third rotating elements (CR3, R3) are drivingly connected to the output member (15), and hydraulic pressure And a plurality of engaging elements that can be engaged / disengaged by supplying / discharging and connected to the first, second, and fourth rotating elements, and capable of selectively forming a plurality of shift speeds by a combination of simultaneous engagement. Mechanism (14, 114) and the engagement required A hydraulic control device (30) capable of supplying and discharging hydraulic pressure, and a control device (20) for electrically controlling the hydraulic control device (30), wherein the control device (20) includes the drive All engagements connected to the second rotating element (CR2, R3, CR2, CR3) or the fourth rotating element (S2, S3, S3) when carrying out inertial running with the source (2) stopped Of the engaging elements (B1, B2, B1, C3, C4) that release the elements (C1, C2, B4, C1, C2, B2) and rotate or stop the first rotating element (R2, S2) Engage at least some engagement elements. According to this configuration, the second rotation element (CR2, R3, CR2, CR3) adjacent to the third rotation element (CR3, R3) connected to the output member (15) corresponding to the gear ratio and the fourth rotation The elements (S2, S3, S3) are prevented from being stopped and fixed. Therefore, the second rotating element (CR2, R3, CR2, CR3) and the fourth rotating element (S2, S3, S3, S3, S3, R3) adjacent to the third rotating element (CR3, R3) having a large output on the velocity diagram. Since none of S3) outputs 0, it is possible to prevent any rotating element from over-rotating beyond the highest speed stage. That is, it is possible to suppress over-rotation of the rotating element during inertial traveling while having the automatic transmission mechanism (14, 114) capable of inertial traveling in the neutral state with the drive source (2) stopped.

  In the vehicle drive device (3) of the first and second embodiments, the control device (20) stops the drive source (2) and performs inertial running when the first rotation element is used. Engage at least some of the engaging elements (B1, B2, B1, C3, C4) that stop (R2, S2). According to this configuration, since the first rotation elements (R2, S2) are fixedly stopped during inertial running, the second rotation elements (CR2, R3, CR2, CR3) adjacent to the third rotation elements (CR3, R3) are used. ) Or the fourth rotation element (S2, S3, S3), the overspeed of the other rotation elements can be suppressed without making the gradient of the speed line steep.

  Moreover, in the vehicle drive device (3) of the first and second embodiments, the control device (20) stops the drive source (2) and performs inertial running to perform the drive source (2 ) Is engaged, at least some of the engaging elements (B1, B2, B1, C3, C4) that rotate the first rotating element (R2, S2) are engaged. According to this configuration, only the engaging element that rotates the first rotating element (R2, S2) is always engaged and retained during coasting, so there is no need to re-engage the clutch according to the vehicle speed. In addition, the engaging operation during inertia traveling is not required, and the fuel consumption can be improved and the original pressure generating unit (50) can be reduced in size.

  Moreover, in the vehicle drive device (3) of the first and second embodiments, the control device (20) stops the drive source (2) and performs inertial running to perform the drive source (2 ) Engages all of the engaging elements (B1, B2, B1, C3, C4) that rotate or stop the first rotating element (R2, S2). According to this configuration, it is possible to improve the responsiveness in returning to the normal traveling at a plurality of shift speeds as compared with the case where all the engaging elements are released during the inertia traveling.

  Further, in the vehicle drive device (3) of the first and second embodiments, the control device (20) is engaged when there is a start request for the drive source (2) during the inertial running. A shift speed that can be formed by using the engaging element is selected, and the selected shift speed is formed after the drive source (2) is started. According to this configuration, it is possible to improve the responsiveness of returning to normal traveling.

  Moreover, in the vehicle drive device (3) of the first and second embodiments, when the drive source (2) is stopped, a source pressure for engaging the at least some of the engagement elements is generated. An original pressure generation unit (50) is provided. According to this configuration, even when the mechanical oil pump is stopped by stopping the driving source (2), the engagement and holding of the engaging elements can be realized.

1 Vehicle 2 Internal combustion engine (drive source)
3 Vehicle Drive Device 13 Input Shaft (Input Member)
14 Transmission mechanism (automatic transmission mechanism)
15 Output shaft (output member)
20 ECU (control device)
30 Hydraulic control device 50 Electric oil pump (original pressure generating unit)
114 Transmission mechanism (automatic transmission mechanism)
B1 First brake (engaging element)
B2 Second brake (engagement element)
B4 Fourth brake (engagement element)
C1 first clutch (engagement element)
C2 Second clutch (engagement element)
C3 3rd clutch (engagement element)
C4 4th clutch (engagement element)
CR2 second carrier (second rotating element)
CR3 third carrier (third rotating element, second rotating element)
DP1 1st planetary gear (input planetary gear)
DP3 3rd planetary gear (planetary gear)
PS planetary gear set R2 2nd ring gear (first rotating element)
R3 3rd ring gear (2nd rotating element, 3rd rotating element)
S2 Second sun gear (fourth rotating element, first rotating element)
S3 Third sun gear (fourth rotating element)
SP1 1st planetary gear (input planetary gear)
SP2 2nd planetary gear (planetary gear)
SP3 3rd planetary gear (planetary gear)

Claims (3)

An input member drivingly connected to a drive source, an output member drivingly connected to a wheel, and a power transmission path from the input member to the output member, and a combination of a plurality of planetary gears, corresponding to the gear ratio. A planetary gear set having first, second, third, and fourth rotating elements arranged in order, and the third rotating element drivingly connected to the output member; An automatic transmission mechanism having a plurality of engagement elements coupled to the first, second, and fourth rotation elements and capable of selectively forming a plurality of shift stages by a simultaneous engagement combination;
A hydraulic control device capable of supplying and discharging hydraulic pressure to and from the engagement element;
A control device for electrically controlling the hydraulic control device,
When the inertial running is performed with the drive source stopped, the control device releases all the engagement elements connected to the second rotation element or the fourth rotation element, and after the drive source stops Engaging all of the engaging elements that rotate or stop the first rotating element;
Vehicle drive device. The control device selects a shift stage that can be formed by using an engaging element that is engaged when the drive source is requested to start during the inertia traveling, and is selected after the drive source is started. The vehicle drive device according to claim 1 , wherein a gear stage is formed . 3. The vehicle drive device according to claim 1 , further comprising an original pressure generating unit that generates an original pressure for engaging the at least a part of the engaging elements when the driving source is stopped . 4.

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