JP2015217887A - Power transmission system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a power transmission system capable of improving fuel economy while suppressing the generation of noise.SOLUTION: A power transmission system 100 comprises: a first shaft 3 to which an engine 10 and a first motor 20 are connected; a second shaft 80 to which a second motor 30 is connected; a third shaft 61 to which an output torque is transmitted from the first shaft 3 and the second shaft 80; and switching means 50 switching over between a first transmission passage for transmitting the output torque of the first shaft 3 to the third shaft 61 via the second shaft 80 and a second transmission passage for directly transmitting the output torque of the first shaft 3 to the third shaft 61. The switching means 50 is provided in the first shaft 3.

Description

  The present invention relates to a power transmission device used in a hybrid vehicle having an engine and an electric motor as drive sources.

  In a hybrid vehicle having an engine and an electric motor as a drive source, a first output shaft connected to the engine and a first output shaft connected in parallel to the first output shaft are connected to the electric motor with respect to the drive shaft connected to the drive wheels. A configuration of a power transmission device that transmits power from at least one of the second output shaft is known.

  In such a configuration, when the torque of the motor is near zero, the gear that rotates integrally with the second output shaft is in a floating state, and the torque transmitted from the first output shaft to the drive shaft varies. In this case, there is a concern that noise such as rattling noise may occur in the gear meshing between the second output shaft and the drive shaft. For this reason, for example, Japanese Unexamined Patent Application Publication No. 2012-017007 (Patent Document 1) discloses a power transmission device that transmits power from a first output shaft to a drive shaft via a second output shaft.

JP 2012-017007 A

  However, in the configuration disclosed in Patent Document 1, it is difficult to select a gear ratio or a travel mode depending on a traveling state, and it is difficult to improve fuel consumption and vibration performance.

  An object of the present invention is to solve the above-described problems, and an object of the present invention is to provide a power transmission device that can improve fuel efficiency while suppressing generation of noise.

  This power transmission device includes a first shaft to which an engine and a first motor are connected, a second shaft to which a second motor is connected, and a third shaft to which output torque from the first shaft and the second shaft is transmitted. Switching means for switching between a first transmission path for transmitting the output torque of the first axis to the third axis via the second axis and a second transmission path for directly transmitting the output torque of the first axis to the third axis With. The switching means is provided on the first shaft.

  By configuring in this way, the transmission path for transmitting the power from the engine to the drive shaft is switched to the first transmission path or the second transmission path by the switching means, so that the transmission efficiency according to the driving state of the vehicle. Therefore, it is possible to select a power transmission path with good quality, so that fuel efficiency can be improved. In the first transmission path, the power from the engine passes through the second shaft connected to the second electric motor, so that noise such as rattling noise can be reduced. In addition, by adopting a configuration in which the switching means is provided, it is not necessary to newly provide a transmission having a brake or a clutch in order to change the speed of the electric motor. In particular, since there are few parts arranged around the first axis, the switching means can be easily arranged. Thus, this power transmission device can improve fuel consumption while suppressing the generation of noise.

  ADVANTAGE OF THE INVENTION According to this invention, the power transmission device which can improve a fuel consumption, suppressing generation | occurrence | production of noise can be provided.

It is a figure which shows the structure of the power transmission device which concerns on Embodiment 1. FIG. It is a figure for demonstrating the 1st transmission path | route of the power transmission device shown in FIG. It is a figure for demonstrating the 2nd transmission path | route of the power transmission device shown in FIG. It is a figure which shows the structure of the power transmission device which concerns on Embodiment 2. FIG.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the following embodiments, the same or common parts are denoted by the same reference numerals in the drawings, and description thereof will not be repeated.

(Embodiment 1)
(Configuration of vehicle and power transmission device)
FIG. 1 is a diagram illustrating a configuration of a power transmission device according to the present embodiment. With reference to FIG. 1, the structure of the power transmission device 100 according to the present embodiment will be described.

  The power transmission device 100 is mounted on the vehicle 1. The vehicle 1 includes an engine 10, a damper 12, a first electric motor 20, and a second electric motor 30. The vehicle 1 is, for example, an FF (front engine / front drive) hybrid vehicle.

  The engine 10 is a known internal combustion engine such as a gasoline engine or a diesel engine. The engine 10 is configured such that the engine rotational speed and the engine torque are changed by electrically controlling an intake air amount, a fuel injection amount, an ignition timing, and the like by an ECU (Electronic Control Unit) (not shown). The damper 12 absorbs torque fluctuations of the engine 10.

  The first motor 20 and the second motor 30 are, for example, three-phase AC rotary motors. The first electric motor 20 includes a rotor 20a and a stator 20b. The rotor 20a has a hollow cylindrical shape, and the inner peripheral side thereof is fixed to the rotor shaft 22 so that the rotation centers coincide with each other.

  The first electric motor 20 has a function as a generator that generates electric power using the power of the engine 10. The first electric motor 20 also has a function as a starter for starting the engine 10 by rotating the crankshaft of the engine 10.

  The second electric motor 30 includes a rotor 30a and a stator 30b. The rotor 30a has a hollow cylindrical shape, and is fixed to the hollow rotor shaft 32 so that the center of rotation coincides with the inner peripheral side thereof.

  Second electric motor 30 applies driving force to driving wheels (not shown) connected to power transmission device 100 using at least one of electric power of a battery (not shown) or electric power generated by first electric motor 20. It functions as a drive motor. Moreover, the 2nd electric motor 30 also has a function as a generator which charges a battery using the electric power generated by regenerative braking.

  The power transmission device 100 includes a first gear set 2, a second gear set 60, and a third gear set 70. Note that the rotating body such as various rotating shafts provided in the power transmission device 100 shown in FIG. 1 can be freely rotated by being connected to a bearing portion such as a bearing provided at a predetermined position or another shaft or rotating body. Supported.

  The first gear set 2 includes a first shaft 3 connected to the engine 10 and the first electric motor 20, a differential mechanism 40, and a switching unit 50. The first shaft 3 includes a cylindrical shaft 44 connected to the engine output shaft 14 of the engine 10, the rotor shaft 22 of the first electric motor 20, and the ring gear 43 of the differential mechanism 40.

  The differential mechanism 40 is a power distribution mechanism that distributes the power from the engine 10 to the first electric motor 20 and the second gear set 60 via the switching means 50. The differential mechanism 40 is a planetary gear mechanism including a sun gear 41, a pinion gear 42, a ring gear 43, and a carrier CA.

  The pinion gear 42 meshes with each of the sun gear 41 and the ring gear 43. The carrier CA supports the pinion gear 42 so as to be capable of rotating, and is connected to the engine output shaft 14 of the engine 10 via the damper 12.

  The sun gear 41 is connected to the rotor shaft 22 of the first electric motor 20. A gear that meshes with the pinion gear 42 is provided on the inner peripheral side of the ring gear 43. The ring gear 43 has a cylindrical shape. One end of the ring gear 43 located on the engine 10 side is coupled to a shaft 44 extending toward the engine 10 side. The rotation center of the shaft 44 coincides with the rotation center of the engine output shaft 14.

  The first gear set 2 and the first electric motor 20 form an electric transmission unit. The electric transmission unit changes the rotational speed of the engine output shaft 14 by controlling the operating state of the first electric motor 20, and transmits the power to the second gear set 60 via the switching means 50.

  The switching unit 50 includes a first rotating member 51, a second rotating member 52, a third rotating member 53, and an engaging member 56. The first rotating member 51 is provided so as to protrude outward in the radial direction of the shaft 44 and rotates integrally with the shaft 44. The first rotating member 51 is provided at the approximate center of the shaft 44.

  The second rotating member 52 is provided on the engine 10 side with respect to the first rotating member 51. The second rotating member 52 is provided to be rotatable relative to the shaft 44 by a bearing portion 54 provided between the second rotating member 52 and the shaft 44. The second rotating member 52 rotates integrally with the first rotating member 51 by being engaged with the first rotating member 51 by the engaging member 56. The second rotating member 52 has a gear portion 52a that meshes with an idler gear 62 of a second gear set 60 described later.

  The third rotating member 53 is provided on the differential mechanism 40 side with respect to the first rotating member 51. The third rotating member 53 is provided to be rotatable relative to the shaft 44 by a bearing portion 55 provided between the third rotating member 53 and the shaft 44. The third rotating member 53 rotates integrally with the first rotating member 51 by being engaged with the first rotating member 51 by the engaging member 56. The 3rd rotation member 53 has the gear part 53a which meshes with the output driven gear 65 of the 2nd gear set 60 mentioned later.

  The engagement member 56 is provided so as to be movable in the axial direction of the engine output shaft 14 (DR1 direction in the drawing). When the engaging member 56 is in the first position (A position in the figure), the engaging member 56 engages the first rotating member 51 and the second rotating member 52. When the engaging member 56 is in the second position (B position in the figure), the first rotating member 51 and the third rotating member 53 are engaged.

  The engaging member 56 is switched from one of the first position (position A) and the second position (position B) to the other position using a hydraulic or electric actuator. The operation of the actuator is controlled by an ECU (not shown), for example.

  The second gear set 60 includes a counter shaft 61 as a third shaft, an idler gear 62, an output driven gear 65, and a final gear 63. The counter shaft 61 is disposed in parallel with the first shaft 3 (the rotor shaft 22, the engine output shaft 14, and the shaft 44). Output torque from the first shaft 3 and a second shaft 80 described later is transmitted to the counter shaft 61.

  The idler gear 62 is provided so as to be relatively rotatable by a bearing portion 64 provided between the idler gear 62 and the counter shaft 61. The idler gear 62 meshes with the gear portion 52a of the second rotating member 52 described above and the counter driven gear 72 of the third gear set 70 described later.

  The output driven gear 65 and the final gear 63 are fixed to the counter shaft 61 and rotate integrally with the counter shaft 61. The output driven gear 65 meshes with each of the gear portion 53a of the third rotating member 53 and the output gear 75 of the third gear set 70 described later.

  The final gear 63 is provided between the idler gear 62 and the output driven gear 65 in the axial direction of the counter shaft 61. The final gear 63 meshes with a gear portion (not shown) connected to the drive wheel.

  The third gear set 70 includes a second shaft 80, a counter driven gear 72, and an output gear 75 connected to the second electric motor 30. The second shaft 80 includes a rotor shaft 32 of the second electric motor 30 having a cylindrical shape, and a connecting shaft connected to the rotor shaft 32. The connecting shaft includes a first inner peripheral shaft 71 and a second inner peripheral shaft 74.

  One end side of the first inner peripheral shaft 71 is connected to the rotor shaft 32 by spline fitting at the first fitting position so that the rotation center coincides with the rotor shaft 32. A counter driven gear 72 is fixed to the other end side of the first inner peripheral shaft 71.

  One end side of the second inner peripheral shaft 74 is connected by spline fitting at the second fitting position so that the rotation center coincides with the rotor shaft 32. An output gear 75 is fixed to the other end side of the second inner peripheral shaft 74.

  The second inner peripheral shaft 74 is a hollow rotating shaft, and the first inner peripheral shaft 71 is provided so as to penetrate the inside of the second inner peripheral shaft 74 in the axial direction. The first fitting position at which one end side of the first inner peripheral shaft 71 is fitted is the other end of the rotor shaft 32 than the second fitting position at which one end side of the second inner peripheral shaft 74 is fitted. Become the side.

  The counter driven gear 72 rotates integrally with the first inner peripheral shaft 71. The counter driven gear 72 meshes with the idler gear 62 described above. The output gear 75 rotates integrally with the second inner peripheral shaft 74. The output gear 75 meshes with the output driven gear 65 described above.

(Power transmission path)
In the vehicle 1 including the power transmission device 100 having the above-described configuration, the output torque of the first shaft 3 is changed to the third via the second shaft 80 depending on the position of the engaging member 56 of the switching unit 50. The first transmission path for transmitting to the counter shaft 61 as the shaft and the second transmission path for directly transmitting the output torque of the first shaft 3 to the counter shaft 61 as the third axis are switched.

  2 and 3 are diagrams for explaining a first transmission path and a second transmission path of the power transmission device shown in FIG. The first transmission path and the second transmission path will be described with reference to FIGS.

  As shown in FIG. 2, the first transmission path is formed when the engaging member 56 of the switching means 50 is in the first position A. As shown by the solid line in FIG. 2, the first transmission path uses the output torque of the first shaft 3 (the power distributed by the differential mechanism 40) to the second rotating member 52, the idler gear 62, the counter driven gear 72, the second The shaft 80 (more specifically, the first inner peripheral shaft 71, the rotor shaft 32 and the second inner peripheral shaft 74), the output gear 75, and the output driven gear 65 are transmitted to the counter shaft 61 via this order. The route to be included.

  Further, when the first transmission path is formed, the power of the second electric motor 30 is transmitted to the second shaft 80 (more specifically, the rotor shaft 32 and the second inner shaft, as shown by a one-dot chain line in FIG. 2). A third transmission path is formed for transmission to the countershaft 61 via the peripheral shaft 74), the output gear 75 and the output driven gear 65.

  As shown in FIG. 3, the second transmission path is formed when the engaging member 56 of the switching unit 50 is in the second position B. As shown by a broken line in FIG. 3, the second transmission path passes through the third rotating member 53 and the output driven gear 65 without passing through the second shaft 80, and the output torque (differential mechanism) of the first shaft 3. Including a path for transmitting the power distributed by the motor 40 to the counter shaft 61.

  Further, when the second transmission path is formed, the power of the second electric motor 30 is transmitted to the second shaft 80 (more specifically, the rotor shaft 32 and the second inner circumference as shown by a one-dot chain line in FIG. 3). A fourth transmission path is formed to transmit to the countershaft 61 via the shaft 74), the output gear 75, and the output driven gear 65.

  The engagement member 56 of the switching means 50 is moved according to the speed of the vehicle, for example. For example, when the speed of the vehicle is higher than a predetermined value, the above-described actuator is controlled so that the engaging member 56 is located at the second position B. Further, when the vehicle speed is lower than a predetermined value, the above-described actuator is controlled so that the engaging member 56 is positioned at the first position A.

  Here, the number of gears of the idler gear 62 of the second gear set 60 and the number of gears of the counter driven gear 72 of the third gear set 70 are different. The number of gears of the output driven gear 65 of the second gear set 60 and the third gear set 70 This is different from the number of gears of the output gear 75. In this case, the first gear ratio between the idler gear 62 and the counter driven gear 72 is preferably smaller than the second gear ratio between the output driven gear 65 and the output gear 75.

  As described above, when the vehicle speed is higher than a predetermined value and the engaging member 56 of the switching means 50 moves to the second position B, the gear portion 53a of the third rotating member 53 and the output driven gear are used. The second transmission path is formed by meshing with 65. As a result, the power of the engine 10 is transmitted directly to the counter shaft 61 via the output driven gear 65 without passing through the second shaft 80. In a high vehicle speed region where the rotational speed of the engine 10 is high, torque fluctuations hardly occur in the engine 10. For this reason, even when power is transmitted through the second transmission path, rattling noise in the third gear set 70 is less likely to occur. Moreover, the power transmission efficiency is improved by directly transmitting the power from the engine. Thereby, fuel consumption can be improved.

  Further, when the second transmission path is formed, the speed ratio of the rotation of the counter shaft 61 with respect to the rotation of the second electric motor 30 is set based on the difference between the first gear ratio and the second gear ratio described above. Compared to the case where the transmission path is formed, the transmission path can be made smaller (high speed side). For this reason, when the second transmission path is formed, the maximum speed of the vehicle can be increased as compared with the case where the first transmission path is formed. In addition, since the vehicle speed at which the power transmission efficiency is highest when the second transmission path is formed can be set in the high vehicle speed region, fuel efficiency can be improved in the high vehicle speed region. That is, by having the first gear ratio and the second gear ratio, the maximum vehicle speed can be improved and a good point of engine thermal efficiency can be used.

  On the other hand, when the vehicle speed is lower than a predetermined value and the engaging member 56 of the switching means 50 moves to the first position A, the idler gear 62, the counter driven gear 72, the second shaft 80, the output gear 75. A first transmission path is formed by the output driven gear 65.

  By forming the first transmission path, the power of the engine 10 is transmitted to the final gear 63 via each shaft, each gear, and each connecting portion of the third gear set 70, so that the torque of the second motor 30 is zero. It is possible to suppress the generation of noise such as rattling noise that may occur due to the proximity.

  Further, by forming the first transmission path, the transmission gear ratio of the rotation of the counter shaft 61 with respect to the rotation of the second electric motor 30 can be made larger (low speed side) than the transmission gear ratio when the second transmission path is formed. Therefore, the driving force by the second electric motor 30 can be sufficiently ensured in the low vehicle speed region. Further, since the vehicle speed at which the power transmission efficiency becomes highest when the first transmission path is formed can be set in the low vehicle speed region, the fuel efficiency can be improved in the low vehicle speed region.

  As described above, the power transmission device 100 according to the present embodiment switches the power transmission path for transmitting the power from the engine 10 to the axle according to the driving state such as the speed of the vehicle. Fuel consumption can be improved while suppressing the occurrence.

(Embodiment 2)
FIG. 4 is a diagram showing a configuration of the power transmission device according to the present embodiment. A power transmission device 100A according to the present embodiment will be described with reference to FIG.

  As shown in FIG. 4, the power transmission device 100 </ b> A according to the present embodiment differs from the power transmission device 100 according to the first embodiment in the configuration of the switching unit 50 </ b> A. Other configurations are almost the same.

  The switching means 50A is configured to be supported by the transmission case 90. For example, the switching means 50A includes a brake 91 and clutches 92 and 93. The brake 91 corresponds to an engaging element for fixing the rotating element (first rotating member 51 </ b> A) of the first shaft 3 to the transmission case 90.

  The brake 91 has the same configuration as a known multi-plate brake. When the brake 91 is operated to the engaged state, the first rotating member 51A is locked so as not to rotate. On the other hand, when the brake 91 is operated to the released state, the first rotating member 51A can freely rotate.

  For example, when the brake 91 is in the engaged state, the first rotating member 51A cannot rotate, and the second rotating member 52A and the third rotating member 53A can rotate relative to the first shaft 3. It becomes. In this case, the first electric motor 20 can generate electric power using the power of the engine 10, and the second electric motor 30 can be driven using the electric power generated by the first electric motor 20 to drive the vehicle 1A. You can run a series. As a result, the retreat travel distance can be ensured.

  The clutches 92 and 93 are configured as well-known multi-plate clutches. When the clutch 92 is operated to the engaged state, the first rotating member 51A and the second rotating member 52A are connected. Accordingly, the first rotating member 51A and the second rotating member 52A rotate integrally. When the clutch 93 is operated to the engaged state, the first rotating member 51A and the third rotating member 53A are connected. Accordingly, the first rotating member 51A and the third rotating member 53A rotate integrally.

  By having such a configuration, the power transmission device 100A according to the present embodiment provides the same effects as those of the power transmission device 100 according to the first embodiment, and the support rigidity of the switching means 50A. Can be increased. Also, the traveling mode can be controlled.

  Although the embodiments of the present invention have been described above, the embodiments disclosed herein are illustrative and non-restrictive in every respect. The scope of the present invention is defined by the terms of the claims, and includes meanings equivalent to the terms of the claims and all modifications within the scope.

  DESCRIPTION OF SYMBOLS 1 Vehicle, 1st gear set, 3 1st axis | shaft, 10 Engine, 12 damper, 14 Engine output shaft, 20 1st electric motor, 20a rotor, 20b Stator, 22 Rotor shaft, 30 2nd electric motor, 30a Rotor, 30b Stator, 32 rotor shaft, 40 differential mechanism, 41 sun gear, 42 pinion gear, 43 ring gear, 44 shaft, 50, 50A switching means, 51, 51A first rotating member, 52, 52A second rotating member, 52a gear portion, 53, 53A Third rotating member, 53a Gear portion, 54, 55 Bearing portion, 56 Engaging member, 60 Second gear set, 61 Counter shaft, 62 Idler gear, 63 Final gear, 64 Bearing portion, 65 Output driven gear, 70 Third gear set, 71 1st inner shaft, 72 Pointer driven gear, 74 second inner shaft, 75 output gear, 80 second shaft, 90 transmission case, 100, 100A power transmission device.

Claims (1)

A first shaft to which the engine and the first electric motor are connected;
A second shaft to which a second electric motor is connected;
A third shaft to which output torque from the first shaft and the second shaft is transmitted;
A first transmission path for transmitting the output torque of the first axis to the third axis via the second axis; and a second transmission path for directly transmitting the output torque of the first axis to the third axis. Switching means for switching,
The switching means is a power transmission device provided on the first shaft.

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