JP2010269692A - Driving device of hybrid vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a driving device of a hybrid vehicle that can suppress ineffectual energy consumption at the time of switching a driving mode, and can switch the driving mode while maintaining a power transmission to an output member. <P>SOLUTION: The driving device 10 includes a clutch 21 for switching between an engaged state where a ring gear R1 of a first planetary gear mechanism 15 and a ring gear R2 of a second planetary gear mechanism 16 are coupled and a released state where the coupling is released, and a brake 22 for switching between a braking state where the ring gear R2 of the second planetary gear mechanism 16 is braked so as not to be rotatable and a released state where the braking is released. The driving device 10 can switch a driving mode between a first driving mode where the clutch 21 is released and the brake 22 is braked and a second driving mode where the clutch 21 is engaged and the brake 22 is released. The driving device 10 also includes a one-way clutch 20 for inhibiting a rotation of an output shaft 11a of an engine 11 in a predetermined direction. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a drive device for a hybrid vehicle in which an internal combustion engine and an electric motor are provided as power sources, and power output from the power sources is shifted by a plurality of differential mechanisms and transmitted to drive wheels.

  2. Description of the Related Art As a drive device for a hybrid vehicle, there is known a drive device in which an internal combustion engine and an electric motor are mounted as power sources, and power output from these power sources is shifted by a plurality of differential mechanisms and transmitted to drive wheels. For example, a sun gear is a first motor generator, a carrier is an internal combustion engine, a ring gear is connected to an output gear, a first planetary gear mechanism, a sun gear is a second motor generator, and a carrier is a ring of the first planetary gear mechanism. 2. Description of the Related Art There is known a drive device that includes a second planetary gear mechanism that is connected to a gear and an output gear, a ring gear that can be restrained by a brake, and a sun gear of a first planetary gear mechanism that can be interrupted by a clutch (Patent Document 1). reference). In this drive device, the clutch is disengaged and the ring gear of the second planetary gear mechanism is restrained to be non-rotatable by a brake, thereby switching to the low speed mode in which the second planetary gear mechanism functions as a speed reducer. Also, the two planetary gear mechanisms function as one differential mechanism having four rotating elements by releasing the brake and connecting the ring gear of the second planetary gear mechanism and the sun gear of the first planetary gear mechanism with a clutch. Switch to high speed mode. In addition, there is Patent Document 2 as a prior art document related to the present invention.

JP 2008-114811 A JP 2007-118719 A

  In the drive device of Patent Document 1, when the vehicle is running with the power output from at least one of the first motor generator and the second motor generator, the drive wheel is switched from the low speed mode to the high speed mode. There is a risk that the power transmission to the vehicle will be interrupted temporarily or the energy efficiency of the vehicle will deteriorate. When the drive mode is switched from the low speed mode to the high speed mode in this drive device, it is necessary to match the rotation speeds of the ring gear of the second planetary gear mechanism and the sun gear of the first planetary gear mechanism in order to engage the clutch. At this time, if the brake is released in order to change the rotation speed of the ring gear of the second planetary gear mechanism, a reaction force against the output torque of each motor generator is not generated. Therefore, the output torque of each motor generator is not transmitted to the output gear, and there is a possibility that power transmission to the drive wheels is temporarily interrupted. On the other hand, when changing the rotation speed of the sun gear of the first planetary gear mechanism, it is necessary to increase the rotation speed of the internal combustion engine with the first electric motor. For this reason, energy is wasted, and the energy efficiency of the vehicle may be deteriorated.

  Accordingly, an object of the present invention is to provide a drive device for a hybrid vehicle that can suppress wasteful energy consumption when switching the drive mode and can switch the drive mode while maintaining power transmission to the output member. To do.

  A drive device for a hybrid vehicle of the present invention includes a first rotating element, a second rotating element, and a third rotating element that are capable of differentially rotating with each other, the first rotating element being connected to an output shaft of the internal combustion engine, A first differential mechanism in which the second rotary element is connected to the output member, and the third rotary element is connected to the first electric motor; a first rotary element, a second rotary element, and a third differentially rotatable relative to each other; A second differential mechanism having a rotary element, wherein the first rotary element is connected to the second electric motor, and the second rotary element is connected to the second rotary element of the first differential mechanism; and the first differential Switching between an engaged state in which the third rotating element of the mechanism and a third rotating element of the second differential mechanism are coupled so that power can be transmitted between these rotating elements, and a released state in which the coupling is released A possible clutch means and a braking state in which the third rotating element of the second differential mechanism is braked non-rotatably Brake means switchable to a brake release state for releasing the braking, and a first drive mode in which the clutch means is in the released state and the brake means is in the brake state, and the clutch means is in the brake state. In a hybrid vehicle drive device capable of switching a drive mode to a second drive mode in an engaged state and in which the brake means is in a brake released state, the hybrid vehicle includes the first electric motor and the second electric motor. When the drive mode is switched from one of the first drive mode or the second drive mode to the other when traveling with power output from at least one of the output shaft of the internal combustion engine, Rotation limiting means for prohibiting rotation in the direction is further provided.

  According to the drive device of the present invention, the rotation restricting means can inhibit the output shaft of the internal combustion engine from rotating in a predetermined direction. Therefore, the rotation restricting means can generate a reaction force against the output torque of each electric motor. it can. Therefore, it is possible to prevent the power transmission to the output member from being interrupted. Therefore, the drive mode can be switched while maintaining the power transmission to the output member. Further, when it is not necessary to start the internal combustion engine, it is not necessary to rotate the output shaft of the internal combustion engine with the electric motor when switching the drive mode, so that wasteful consumption of energy can be prevented.

  In one aspect of the hybrid vehicle drive device of the present invention, the rotation limiting means prohibits the output shaft of the internal combustion engine from rotating in the predetermined direction and rotates in the opposite direction opposite to the predetermined direction. This may be an allowed one-way clutch (claim 2). In this case, since it is not necessary to control the rotation limiting means from the outside, the control when switching the drive mode can be simplified.

  In one mode of the hybrid vehicle driving device of the present invention, when the internal combustion engine is stopped and the hybrid vehicle is running with power output from at least one of the first electric motor and the second electric motor. When a predetermined start condition for starting the internal combustion engine is satisfied while switching the drive mode from the first drive mode to the second drive mode, the brake means is first switched to the brake release state, and then The output torque of the second electric motor is controlled so that the rotation speed of the output member is maintained at a predetermined rotation speed, and the clutch means is switched to the engaged state, and then the reaction force against the output torque of the second electric motor is changed. Control means for controlling the output torque of the first electric motor so as to increase the rotational speed of the internal combustion engine while being generated. Good (claim 3). In this case, the rotational speed of the internal combustion engine can be increased while generating a reaction force with respect to the output torque of the second motor by the first motor, so that the internal combustion engine can be started while outputting power to the output member.

  In this embodiment, the clutch means transmits power between the third rotating element of the first differential mechanism and the third rotating element of the second differential mechanism using frictional force in the engaged state. And performing a power transmission between the third rotating element of the first differential mechanism and the third rotating element of the second differential mechanism by adjusting the frictional force, and a rotational speed difference between the rotating elements. The control means controls the output torque of the first electric motor so that the rotational speed of the internal combustion engine increases while generating a reaction force against the output torque of the second electric motor. The operation of the clutch means may be controlled so that a rotational speed difference is generated between the third rotating element of the first differential mechanism and the third rotating element of the second differential mechanism. ). In this case, even if the clutch means is switched to the engaged state, the rotation speed of the third rotation element of the second differential mechanism can be prevented from changing suddenly to the rotation speed of the third rotation element of the first differential mechanism. Therefore, it is possible to switch the drive mode while suppressing fluctuations in the rotation speed of the output member.

  As described above, according to the hybrid vehicle drive device of the present invention, the rotation limiting means can generate a reaction force against the output torque of each electric motor, so that power transmission to the output member is maintained. The drive mode can be switched. Further, when there is no need to start the internal combustion engine, it is not necessary to rotate the output shaft of the internal combustion engine with the electric motor when switching the drive mode, so that wasteful consumption of energy can be prevented.

The skeleton figure of the drive device which concerns on the 1st form of this invention. The figure which shows an example of the change of the alignment chart of a power division mechanism when the drive mode of the power division mechanism of FIG. 1 is switched from the 1st drive mode to the 2nd drive mode. The figure which shows the alignment chart of a power split mechanism in the case of starting an internal combustion engine, switching the drive mode of the power split mechanism of FIG. 1 from a 1st drive mode to a 2nd drive mode. The skeleton figure of the drive device which concerns on the 2nd form of this invention. The figure which expands and shows the dog clutch of FIG. The figure which shows an example of the change of the alignment chart of a power division mechanism when the drive mode of the power division mechanism of FIG. 4 is switched from the 1st drive mode to the 2nd drive mode.

(First form)
FIG. 1 shows a skeleton diagram of a driving apparatus according to the first embodiment of the present invention. The drive device 10 is mounted on the hybrid vehicle 1 and includes an internal combustion engine (hereinafter sometimes referred to as an engine) 11 and a first motor generator (hereinafter simply referred to as a first MG) as a first electric motor. And a second motor generator (hereinafter sometimes abbreviated as second MG) 13 as a second electric motor. Since the engine 11 is a well-known engine mounted as a power source in a hybrid vehicle, a detailed description thereof is omitted. The first MG 12 includes a stator 12a that is fixed to the case 2 so as not to rotate, and a rotor 12b that is coaxially disposed on the inner peripheral side of the stator 12a. Similarly, the second MG 13 includes a stator 13a that is non-rotatably fixed to the case 2 and a rotor 13b that is coaxially disposed on the inner peripheral side of the stator 13a. The first MG 12 and the second MG 13 are well-known ones that function as an electric motor and a generator, respectively, and thus detailed description thereof is omitted.

  The engine 11, the first MG 12, and the second MG 13 are connected to the power split mechanism 14, respectively. Power split device 14 switches the connection state of engine 11, first MG 12, and second MG 13 to switch the transmission destination of power output from engine 11, first MG 12, and second MG 13. An output gear 4 as an output member for outputting power to the drive wheels 3 of the vehicle 1 is connected to the power split mechanism 14. In the power transmission path from the power split mechanism 14 to the drive wheel 3, a counter shaft 7 provided so that the counter gear 5 and the drive gear 6 rotate integrally, and a differential mechanism 8 to which the rotation of the drive gear 6 is transmitted. And a drive shaft 9 are provided. The counter shaft 7 is provided so that the counter gear 5 meshes with the output gear 4. Therefore, the power output from the power split mechanism 14 is transmitted to the differential mechanism 8 via the output gear 4, the counter gear 5, the counter shaft 7, and the drive gear 6. The power transmitted to the differential mechanism 8 is then transmitted to the drive wheels 3 via the drive shaft 9.

  The power split mechanism 14 includes a first planetary gear mechanism 15 as a first differential mechanism and a second planetary gear mechanism 16 as a second differential mechanism. Each of the first planetary gear mechanism 15 and the second planetary gear mechanism 16 is a single pinion type planetary gear mechanism. The first planetary gear mechanism 15 includes a sun gear (hereinafter also referred to as a first sun gear) S1 that is an external gear, and a ring gear that is an internal gear disposed coaxially with the sun gear S1. Hereinafter, it may be referred to as a first ring gear.) A carrier (hereinafter referred to as a first carrier) that holds R1 and a pinion gear P1 meshing with these gears S1, R1 so as to be capable of rotating and revolving around the sun gear S1. C1). Similarly, the second planetary gear mechanism 16 includes a sun gear (hereinafter, also referred to as a second sun gear) S2 that is an external gear, and a ring that is an internal gear that is disposed coaxially with the sun gear S2. A carrier (hereinafter referred to as a second ring gear) R2 and a pinion gear P2 meshing with these gears S2 and R2 and capable of rotating around the sun gear S2 (hereinafter referred to as a second carrier). And C2.

  The first sun gear S <b> 1 is coupled to rotate integrally with a rotating shaft 17 that is rotatably supported by the case 2. As shown in this figure, one end of the rotating shaft 17 is connected to the output shaft 11 a of the engine 11 via a damper 18. Note that the damper 18 is a well-known one that can absorb the torque fluctuation of the engine 11, and therefore a detailed description thereof is omitted. On the other hand, the other end of the rotating shaft 17 is connected to an oil pump 19. A one-way clutch 20 is provided on the rotating shaft 17. The one-way clutch 20 allows the rotation shaft 17 to rotate in a predetermined forward rotation direction and prevents the rotation shaft 17 from rotating in the reverse rotation direction opposite to the normal rotation direction. In the forward rotation direction, a direction in which the output shaft 11a of the engine 11 rotates during operation of the engine 11 is set.

  The first ring gear R1 is connected to the rotor 12b of the first MG 12. The first carrier C <b> 1 and the second carrier C <b> 2 are connected to the output gear 4. The second sun gear S2 is connected to the rotor 13b of the second MG 13. The second ring gear R2 is connected to the first ring gear R1 via a clutch 21 as clutch means. The clutch 21 includes a first engagement member 21a and a second engagement member 21b, and is a well-known one that switches contact and separation of the engagement members 21a and 21b with an actuator (not shown). The first engagement member 21a is provided in the first ring gear R1, and the second engagement member 21b is provided in the second ring gear R2. Therefore, when the engaging members 21a and 21b are brought into contact with each other, power transmission between the first ring gear R1 and the second ring gear R2 can be performed using the frictional force. At this time, the clutch 21 adjusts the frictional force between the engaging members 21a and 21b by an actuator, and transmits power between them while generating a rotational speed difference between the engaging members 21a and 21b. it can. Hereinafter, the state in which the engaging members 21a and 21b are brought into contact with each other in this way is referred to as an engaged state. The state where the engaging members 21a and 21b are separated from each other is referred to as a released state. The second ring gear R2 is provided with a brake 22 as brake means. The brake 22 is provided so as to be switchable between a braking state in which the second ring gear R2 is braked so as not to rotate and a braking release state in which the braking is released.

  By connecting the rotating elements of the planetary gear mechanisms 15 and 16 in this way, in the first embodiment, the first sun gear S1 is the first rotating element of the first differential mechanism of the present invention. The carrier C1 corresponds to the second rotating element of the first differential mechanism of the present invention, and the first ring gear R1 corresponds to the third rotating element of the first differential mechanism of the present invention. The second sun gear S2 is the first rotating element of the second differential mechanism of the present invention, the second carrier C2 is the second rotating element of the second differential mechanism of the present invention, and the second ring gear R2 is the present invention. This corresponds to the third rotation element of the second differential mechanism.

  In this power split mechanism 14, the clutch 21 is switched to the disengaged state and the brake 22 is switched to the braking state, thereby restraining the second ring gear R2 so that it cannot rotate, and only the first ring gear R1 is connected to the rotor 12b of the first MG 12. Can be rotated together. In this case, the first planetary gear mechanism 15 and the second planetary gear mechanism 16 function as separate differential mechanisms. Hereinafter, a mode in which the power split mechanism 14 is operated in this state (hereinafter sometimes referred to as a drive mode) is referred to as a first drive mode. On the other hand, when the clutch 21 is switched to the engaged state and the brake 22 is switched to the brake released state, the first ring gear R1 and the second ring gear R2 can be rotated together. Since the first carrier C1 and the second carrier C2 are connected as described above, in this case, the first planetary gear mechanism 15 and the second planetary gear mechanism 16 are used as one differential mechanism having four rotating elements. Can function. Hereinafter, the mode in which the power split mechanism 14 is operated in this state is referred to as a second drive mode. Furthermore, in this power split mechanism 14, since the one-way clutch 20 is provided on the rotating shaft 17, it is possible to prevent the first sun gear S1 from rotating in the reverse direction.

  The operation of the driving device 10 is controlled by the control device 30. The control device 30 is configured as a computer unit including a microprocessor and peripheral devices such as RAM and ROM necessary for its operation, and controls the operation of the drive device 10 in accordance with the traveling state of the vehicle 1 and the operating state of the engine 11. Control. For example, control device 30 controls the operations of engine 11, first MG 12, and second MG 13 according to the traveling state of vehicle 1. More specifically, the control device 30 switches between operation and stop of the engine 11 according to the traveling state of the vehicle 1. Further, the control device 30 switches the drive mode of the power split mechanism 14 in accordance with the traveling state of the vehicle 1. The control device 30 includes, for example, an accelerator position sensor 31 that outputs a signal corresponding to the accelerator position as a sensor for detecting the traveling state of the vehicle 1 and the operating state of the engine 11, and a signal corresponding to the speed of the vehicle 1. Is connected to a vehicle speed sensor 32 or the like. In addition to this, various sensors are connected to the control device 30, but they are not shown.

  The control of the power split device 14 by the control device 30 will be described with reference to FIG. When the drive mode of the power split mechanism 14 is switched from the first drive mode to the second drive mode, the control device 30 first switches the brake 22 to the brake release state, and then switches the first ring gear R1 and the second ring gear R2 to each other. And the clutch 21 is switched to the engaged state. FIG. 2 shows an example of a change in the alignment chart of the power split mechanism 14 when the drive mode of the power split mechanism 14 is thus switched. This figure is an alignment chart when the engine 11 is stopped and the vehicle 1 is traveling on the first MG 12 and the second MG 13. In this figure, the first sun gear S1, the first carrier C1, the first ring gear R1, the second sun gear S2, the second carrier C2, and the second ring gear R2 are denoted by reference numerals S1, C1, R1, S2, C2, respectively. And R2. 2 is the normal rotation direction of the rotation shaft 17 described above, and the rotation direction of “reverse rotation” is the reverse rotation direction of the rotation shaft 17. And the arrow in a figure has shown the torque of each rotation element.

  As shown in the top diagram of FIG. 2, in the first drive mode, the brake 22 is in a braking state, and therefore the rotation speed (the number of rotations) of the second ring gear R2 is fixed to zero. Further, since the clutch 21 is in the released state, the rotation speed of the first ring gear R1 is controlled by the rotor 12b of the first MG 12. Since the engine 11 is stopped, the rotation speed of the first sun gear S1 becomes zero. In this state, a reaction force against the output torque of the second MG 13 is generated by the brake 22, and the output torque of the second MG 13 can be transmitted to the output gear 4. Further, since the first sun gear S1 is prevented from rotating in the reverse rotation direction by the one-way clutch 20, a reaction force against the output torque of the first MG 12 is generated by the one-way clutch 20, and the output torque of the first MG 12 is transmitted to the output gear 4. be able to. In this way, by preventing the first sun gear S1 from rotating in the reverse rotation direction, the one-way clutch 20 functions as the rotation limiting means of the present invention. The reverse direction corresponds to the predetermined direction of the present invention.

  When switching the drive mode to the second drive mode, the brake 22 is first switched from this state to the brake released state, and then the rotational speed of the second ring gear R2 is increased in the forward rotation direction. The second diagram from the top in FIG. 2 shows a collinear diagram of the power split mechanism 14 in the middle of switching the drive mode in this way. As described above, the first sun gear S <b> 1 is prevented from rotating in the reverse rotation direction by the one-way clutch 20. Therefore, even when the brake 22 is in the brake release state, the one-way clutch 20 can generate a reaction force against the output torque of the first MG 12 and the second MG 13. Thereby, the torque output from the first MG 12 and the second MG 13 can be transmitted to the output gear 4.

  Thereafter, as shown in the bottom diagram of FIG. 2, the clutch 21 is switched to the engaged state when the rotational speed of the second ring gear R2 becomes substantially the same as the rotational speed of the first ring gear R1. As a result, the drive mode is switched to the second drive mode.

  On the other hand, when the drive mode is switched from the second drive mode to the first drive mode, the clutch 21 is switched to the released state, then the second MG 13 adjusts the rotational speed of the second ring gear R2 to 0, and then the brake 22 is turned off. Switch to the braking state. Also in this case, after the clutch 21 is switched to the released state, a reaction force against the output torque of the first MG 12 can be generated by the one-way clutch 20, so that the torque of the first MG 12 can be transmitted to the output gear 4.

  As described above, the control device 30 switches between stopping and driving the engine 11 according to the traveling state of the vehicle 1. Therefore, it may be necessary to perform both switching of the drive mode and starting of the engine 11 depending on the traveling state of the vehicle 1. The control device 30 starts the engine 11 while switching the drive mode when predetermined start conditions for performing these two controls are satisfied. FIG. 3 shows an alignment chart of the power split mechanism 14 when the engine 11 is started while switching the drive mode from the first drive mode to the second drive mode. In FIG. 3, the same reference numerals are given to the same parts as those in FIG.

  When starting the engine 11 while switching the drive mode, the control device 30 first switches the brake 22 to the brake release state. Next, the output torque of the second MG 13 is controlled and the clutch 21 is switched to the engaged state so that the rotational speed (rotational speed) of the output gear 4 is maintained at the same predetermined rotational speed as before. At this time, the control device 30 controls the clutch 21 so that power is transmitted between the ring gears R1 and R2 while the rotational speed difference A is generated between the ring gears R1 and R2. Thereafter, control device 30 reduces the rotation speed (rotation speed) of first MG 12. FIG. 3 shows an alignment chart of the power split mechanism 14 at this time. In this case, since the reaction force against the output torque of the second MG 13 can be generated by the first MG 12, the output torque of the second MG 13 can be transmitted to the output gear 4. Further, as shown in this figure, by generating the rotational speed difference A between the ring gears R1 and R2, a sudden change in the rotational speed of the second ring gear R2 can be prevented, so that the rotational speed variation of the output gear 4 can be prevented. Can be suppressed.

  Thereafter, the control device 30 supplies the fuel to the engine 11 and starts the engine 11 when the rotational speed of the engine 11 reaches a rotational speed suitable for starting. Further, the clutch 21 is controlled so that the ring gears R1 and R2 rotate integrally when the rotation speeds of the first ring gear R1 and the second ring gear R2 become substantially the same. Thereby, the engine 11 can be started while switching the drive mode to the second drive mode. By controlling the drive device 10 in this way, the control device 30 functions as the control means of the present invention.

  According to the drive device of the first embodiment, since the one-way clutch 20 is provided on the rotary shaft 17, even if the brake 22 is switched to the brake release state, the reaction force against the output torque of the first MG 12 and the second MG 13 is generated by the one-way clutch 20. Can be generated. Therefore, the power transmission to the output gear 4 can be prevented from being interrupted. Therefore, the drive mode of the power split mechanism 14 can be switched while maintaining the power transmission to the output gear 4. Further, as shown in FIG. 2, when the engine 11 does not need to be started, the drive mode can be switched without increasing the rotation speed of the first sun gear S1, so that wasteful energy is consumed when the drive mode is switched. Can be suppressed.

  Further, according to the drive device of the first embodiment, when starting the engine 11 while switching the drive mode, the clutch 21 is switched to the engaged state and the reaction force against the output torque of the second MG 13 is generated by the first MG 12. While increasing the rotational speed of the engine 11. Therefore, it is possible to start the engine 11 while maintaining power transmission to the output gear 4. At this time, since the clutch 21 is slid so that the rotational speed difference A is generated between the first ring gear R1 and the second ring gear R2, fluctuations in the rotational speed of the output gear 4 can be suppressed.

  Furthermore, according to the driving device of the first embodiment, the vehicle 1 can be driven by the driving forces of both the first MG 12 and the second MG 13. In this case, the maximum torque of the second MG 13 can be reduced as compared with a drive device that uses only one of the MGs, specifically, the second MG 13 for traveling the vehicle. Therefore, the second MG 13 can be reduced in size.

(Second form)
Next, a driving apparatus according to a second embodiment of the present invention will be described with reference to FIGS. FIG. 4 shows a skeleton diagram of the driving device 10 of the second embodiment. 4 that are the same as those in FIG. 1 are denoted by the same reference numerals and description thereof is omitted. As shown in this figure, in the driving device 10 of the second embodiment, the engine 11, the second MG 13, the second planetary gear mechanism 16, the first planetary gear mechanism 15, and the first MG 12 are arranged from one side (the right side in FIG. 4). These are arranged in order. Further, in the driving device 10, the first planetary gear mechanism 15 is a double pinion type planetary gear mechanism having two pinion gears P11 and P12. In the drive device 10, the output shaft 11a of the engine 11 is connected to the first carrier C1. The rotor 12b of the first MG 12 is connected to the first sun gear S1, and the rotor 13b of the second MG 13 is connected to the second sun gear S2. The output gear 4 is connected to the first ring gear R1 and the second carrier C2.

  By connecting the rotating elements of the planetary gear mechanisms 15 and 16 in this way, in the second embodiment, the first carrier C1 is connected to the first rotating element of the first differential mechanism of the present invention. The gear R1 corresponds to the second rotating element of the first differential mechanism of the present invention, and the first sun gear S1 corresponds to the third rotating element of the first differential mechanism of the present invention.

  As shown in this figure, the drive device 10 of the second embodiment includes a dog clutch 40. FIG. 5 shows an enlarged portion of the dog clutch 40. The dog clutch 40 includes an engagement hub 41 that rotates integrally with the second ring gear R2, a brake hub 42 that is non-rotatably fixed to the case 2, and a clutch that rotates integrally with the first sun gear S1 and the rotor 12b of the first MG 12. And a hub 43. As shown in this figure, the brake hub 42 is disposed on one side of the engagement hub 41, and the clutch hub 43 is disposed on the other side of the engagement hub 41.

  Spline teeth are formed on the outer peripheral surfaces of the hubs 41, 42, 43, and a sleeve 44 is engaged with these spline teeth so as to be movable in the left-right direction in FIG. The sleeve 44 has a length that can engage with only the engagement hub 41, and engages with the engagement hub 41 and the brake hub 42 when moved to the right side of FIG. The coupling hub 41 and the clutch hub 43 are provided so as to mesh with each other. Therefore, the second ring gear R2 can be braked so as not to rotate by moving the sleeve 44 to the right in FIG. In this case, the dog clutch 40 functions as the brake means of the present invention. On the other hand, the second ring gear R2 and the first sun gear S1 can be rotated together by moving the sleeve 44 to the left in FIG. In this case, the dog clutch 40 functions as the clutch means of the present invention. Hereinafter, a state in which the sleeve 44 is engaged with only the engagement hub 41 may be referred to as a released state. Further, a state where the sleeve 44 is engaged with the engagement hub 41 and the brake hub 42 may be referred to as a brake state, and a state where the sleeve 44 is engaged with the engagement hub 41 and the clutch hub 43 may be referred to as a clutch state. . As shown in FIG. 4, the operation of the dog clutch 40 is controlled by the control device 30.

  In this drive device 10, when the dog clutch 40 is switched to the brake state, the drive mode of the power split mechanism 14 becomes the first drive mode. On the other hand, when the dog clutch 40 is switched to the clutch state, the drive mode of the power split mechanism 14 becomes the second drive mode. FIG. 6 corresponds to FIG. 2 of the first embodiment, and shows an example of a change in the alignment chart of the power split mechanism 14 when the drive mode of the power split mechanism 14 is switched from the first drive mode to the second drive mode. Show. In FIG. 6, the same parts as those in FIG. As shown in FIG. 6, in this embodiment, the first sun gear S1 is located at the position of the first ring gear R1 in FIG. 2, the first ring gear R1 is located at the position of the first carrier C1, and the first sun gear S1 is located at the position of the first sun gear S1. One carrier C1 is arranged. The rest is the same as FIG.

  As shown in this figure, in the second embodiment, when the drive mode is switched to the second drive mode, the dog clutch 40 is first switched from the brake state to the released state, and then the second MG 13 rotates the rotational speed of the second ring gear R2. Is adjusted to be the same as that of the first ring gear R1. Thereafter, the dog clutch 40 is switched from the released state to the brake state. Also in this embodiment, since the one-way clutch 20 is provided on the rotating shaft 17, the first sun gear S1 is prevented from rotating in the reverse direction as shown in the second drawing from the top in FIG. Therefore, even if the dog clutch 40 is in the released state, the reaction force against the output torque of the first MG 12 and the second MG 13 can be generated by the one-way clutch 20. Therefore, the torque output from the first MG 12 and the second MG 13 can be transmitted to the output gear 4.

  As described above, also in the drive device 10 of the second embodiment, the one-way clutch 20 can generate a reaction force against the output torque of the first MG 12 and the second MG 13, so that power splitting is performed while maintaining power transmission to the output gear 4. The drive mode of the mechanism 14 can be switched. Further, as shown in FIG. 6, since the drive mode can be switched without increasing the rotational speed of the first carrier C1 connected to the engine 11, energy is wasted when switching the drive mode. Can be suppressed. Furthermore, since the vehicle 1 can be driven by the driving forces of both the first MG 12 and the second MG 13, the second MG 13 can be reduced in size.

  This invention is not limited to each form mentioned above, It can implement with a various form. For example, in the drive device of the present invention, the first planetary gear mechanism may be a single pinion type, the second planetary gear mechanism may be a double pinion type, or both the first planetary gear mechanism and the second planetary gear mechanism are double pinion types. But you can. Further, the differential mechanism is not limited to the planetary gear mechanism, and for example, a planetary roller mechanism in which a roller is provided instead of the pinion gear may be provided as the differential mechanism.

  In the drive device of the present invention, a brake may be provided on the rotating shaft instead of the one-way clutch, and the rotating shaft may be restrained to be unrotatable by this brake when the drive mode is switched. Also in this case, the reaction force against the output torque of the first MG and the second MG can be generated by this brake, so that the drive mode can be switched while maintaining the power transmission to the output gear. In this case, the brake provided on the rotating shaft corresponds to the rotation limiting means of the present invention.

1 Hybrid vehicle 4 Output gear (output member)
DESCRIPTION OF SYMBOLS 10 Drive apparatus 11 Internal combustion engine 11a Output shaft 12 1st motor generator (1st electric motor)
13 Second motor generator (second electric motor)
15 First planetary gear mechanism (first differential mechanism)
16 Second planetary gear mechanism (second differential mechanism)
20 One-way clutch (rotation limiting means)
21 Clutch (clutch means)
22 Brake (brake means)
30 Control device (control means)
40 dog clutch (brake means, clutch means)
S1 sun gear (first rotating element of the first differential mechanism, third rotating element of the first differential mechanism)
C1 carrier (second rotating element of the first differential mechanism, first rotating element of the first differential mechanism)
R1 ring gear (the third rotating element of the first differential mechanism, the second rotating element of the first differential mechanism)
S2 Sun gear (first rotating element of the second differential mechanism)
C2 carrier (second rotating element of the second differential mechanism)
R2 ring gear (third rotating element of the second differential mechanism)

Claims (4)

The first rotating element, the second rotating element, and the third rotating element that are differentially rotatable with each other, the first rotating element is connected to the output shaft of the internal combustion engine, and the second rotating element is connected to the output member. A first differential mechanism in which the third rotating element is connected to the first electric motor;
The first rotating element, the second rotating element, and the third rotating element that are differentially rotatable with each other, the first rotating element is connected to the second electric motor, and the second rotating element is connected to the first differential mechanism. A second differential mechanism coupled to the second rotating element;
The engaged state in which the third rotating element of the first differential mechanism and the third rotating element of the second differential mechanism are connected so that power can be transmitted between these rotating elements, and the connection is released. Clutch means switchable to a released state,
Braking means capable of switching the third rotating element of the second differential mechanism to a non-rotatable braking state and a braking release state for releasing the braking, and
A first drive mode in which the clutch means is in the released state and the brake means is in the braking state; a second drive mode in which the clutch means is in the engaged state; and the brake means is in the brake released state. In a drive device for a hybrid vehicle capable of switching between the drive mode and the drive mode,
When the hybrid vehicle is running with power output from at least one of the first electric motor and the second electric motor, the drive mode is changed from one of the first drive mode or the second drive mode to the other. A drive device for a hybrid vehicle, further comprising rotation limiting means for prohibiting the output shaft of the internal combustion engine from rotating in a predetermined direction when switched.   2. The one-way clutch according to claim 1, wherein the rotation limiting unit is a one-way clutch that prohibits the output shaft of the internal combustion engine from rotating in the predetermined direction and allows the output shaft to rotate in a direction opposite to the predetermined direction. Hybrid vehicle drive device.   When the hybrid vehicle is running with the power output from at least one of the first electric motor and the second electric motor after the internal combustion engine is stopped, the drive mode is changed from the first drive mode to the first drive mode. When a predetermined start condition for starting the internal combustion engine while switching to the two-drive mode is satisfied, the brake means is first switched to the brake release state, and then the rotation speed of the output member is maintained at the predetermined rotation speed. And controlling the output torque of the second electric motor and switching the clutch means to the engaged state, and then increasing the rotational speed of the internal combustion engine while generating a reaction force against the output torque of the second electric motor. The drive device for a hybrid vehicle according to claim 1, further comprising control means for controlling an output torque of the first electric motor. The clutch means transmits power between the third rotating element of the first differential mechanism and the third rotating element of the second differential mechanism using frictional force in the engaged state, and Adjusting the frictional force to cause a power difference between the third rotating element of the first differential mechanism and the third rotating element of the second differential mechanism and causing a rotational speed difference between the rotating elements. Is possible,
When the control means controls the output torque of the first motor so as to increase the rotational speed of the internal combustion engine while generating a reaction force against the output torque of the second motor, The drive device for a hybrid vehicle according to claim 3, wherein the operation of the clutch means is controlled so that a rotational speed difference is generated between the three rotation elements and the third rotation element of the second differential mechanism.

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