JP2015134560A - Power transmission device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a power transmission device capable of easily assembling the device.SOLUTION: The power transmission device stores a gear shift part 4, a differential device 10 for connecting the gear shift part 4 and a motor and outputting torque from an output gear 15 and the motor, inside a casing 23. In the power transmission device, the casing 23 opens on an engine side, a partition wall part 51 is formed inside, and the motor is arranged on the opposite side of an engine across the partition wall part 51, a center support 42 of a separate body from the casing 23 is installed more on the engine side from the partition wall part 51 in the casing 23, and the differential device 10 is arranged between the partition wall part 51 and the center support 42. The gear shift part 4 is arranged more on the engine side from the center support 42, and the output gear 15 is rotatably supported by the partition wall part 51 and the center support 42.

Description

  The present invention relates to a device for transmitting power generated by a driving force source, and more particularly to a power transmission device mounted on a vehicle having a plurality of driving force sources having different power generation principles.

  An example of this type of device is described in Patent Document 1. Briefly describing the configuration, a transmission configured to be able to set a low speed side gear ratio and a high speed side gear ratio, a switching mechanism for switching those gear ratios, and torque output from the transmission. A power distribution mechanism that distributes to the first electric motor and the output member is provided. In addition, a second electric motor that transmits torque to the output member is provided. Electric power generated by the first electric motor is supplied to the second electric motor, and the torque output from the second electric motor is added to the output member. It is comprised so that. An engine is connected to the above transmission. The transmission is arranged on the opposite side of the engine with the first electric motor on the same axis as the output shaft of the engine. A power distribution mechanism is disposed between the transmission and the first electric motor, and a switching mechanism is disposed between the engine and the first electric motor. The second electric motor is provided on the side opposite to the engine across the transmission.

JP 2008-120234 A

  In the configuration described in Patent Document 1, as described above, the power distribution mechanism and the transmission are arranged between the first electric motor and the second electric motor. Therefore, when assembling the power transmission device having the above configuration, for example, a power split mechanism and a transmission are assembled to the first electric motor assembled to the casing of the power transmission device. That is, the number of parts and assembly man-hours to be assembled to the first electric motor are large, and as a result, in the configuration described in Patent Document 1, the assembly of the entire apparatus may be complicated.

  The present invention has been made paying attention to the above technical problem, and an object of the present invention is to provide a power transmission device capable of easily assembling the device.

  To achieve the above object, the present invention includes an engine, a transmission unit coupled to the engine and having a gear ratio set in accordance with the engagement and release states of a plurality of engagement mechanisms, and the transmission unit And a motor, and a differential device that outputs torque from an output gear, wherein the transmission, the differential device, and the motor are housed in a casing. The partition is formed on the engine side and a partition is formed therein, and the motor is disposed on the same axis as the output shaft of the engine and on the opposite side of the engine across the partition, and the partition in the casing A center support separate from the casing is attached to the engine side, and the differential device is between the partition wall and the center support. The transmission shaft is disposed on the same axis as the output shaft, the transmission portion is disposed on the engine side of the center support and on the same axis as the output shaft, and the output gear is formed by the partition portion and the center support. It is characterized by being rotatably supported.

  In the present invention, the transmission unit is constituted by a double-pinion type planetary gear mechanism, and the engagement mechanism selects a clutch that selectively connects a sun gear and a carrier of the planetary gear mechanism, and the sun gear. And an oil passage for supplying a hydraulic pressure for engaging the clutch to the center support, and another oil passage for supplying a hydraulic pressure for engaging the brake. And may be formed.

  Furthermore, in the present invention, the brake may be disposed on the outer peripheral side of the transmission unit in the radial direction of the output shaft.

  According to this invention, when assembling the power transmission device, for example, first, the motor is assembled on the opposite side of the engine across the partition wall portion of the casing. Thereafter, the transmission unit is assembled, and the assembled transmission unit and the plurality of engagement mechanisms are assembled to the center support. Separately, a differential device is disposed on the engine side of the partition wall, and this is connected to the motor so that power can be transmitted, and one end of the output gear is rotatably attached to the partition. Next, the center support configured as described above is assembled to the casing, and the other end of the output gear is rotatably attached to the partition wall side of the center support. Further, the transmission unit and the differential device are coupled so as to be able to transmit power. As described above, according to the present invention, the components of the power transmission device can be assembled sequentially from the partition wall side to the engine side of the casing. In this case, the transmission unit having a large number of parts can be assembled to the center support, that is, the transmission unit and the engagement mechanism can be sub-assembled in advance and assembled to the casing. As a result, it is possible to easily connect the transmission, the differential device, the motor, and the like to a state where power can be transmitted, and it is possible to improve the assemblability and productivity of the power transmission device according to the present invention.

  In addition, oil passages are formed in the center support for supplying hydraulic pressure for selectively engaging the clutch and the brake. These oil passages can be easily formed by, for example, drilling a center support. That is, it is possible to effectively utilize the space and to suppress an increase in the number of parts due to providing each oil passage as a separate body. Furthermore, since the brake is disposed on the outer periphery of the transmission unit, the space on the outer periphery side of the transmission unit can be effectively utilized.

It is sectional drawing which expands and shows a part in an example of the power transmission device which concerns on this invention. It is a figure for demonstrating the position of the differential gear in an example of the power transmission device which concerns on this invention. FIG. 2 is a skeleton diagram for explaining a power train of a hybrid vehicle that can be a subject of the present invention, and is a diagram showing an example of a power train to be mounted on a front engine / front drive hybrid vehicle.

  Next, the present invention will be specifically described. FIG. 3 is a skeleton diagram for explaining a power train of a hybrid vehicle that can be an object of the present invention, and shows an example of a power train to be mounted on a front engine / front drive hybrid vehicle. It is. The vehicle shown here is a so-called two-motor hybrid vehicle having an engine (ENG) 1 and two motor generators, a first motor / generator (MG1) 2 and a second motor / generator (MG2) 3. is there. As shown in FIG. 3, on the output side of the engine 1, a transmission unit 4 that can change gears at least in two steps of height is provided. The transmission unit 4 is configured by a differential mechanism having three rotating elements, and in the example shown here, is configured by a double pinion type planetary gear mechanism.

  The double-pinion type planetary gear mechanism includes a sun gear 5 that is an external gear, a ring gear 6 that is an internal gear disposed concentrically with the sun gear 5, and a first pinion gear 7 that meshes with the sun gear 5. The second pinion gear 8 meshed with the first pinion gear 7 and the ring gear 6 and the carrier 9 holding the pinion gears 7 and 8 so as to rotate and revolve. The ring gear 6 is connected to the output shaft 1 a of the engine 1. The carrier 9 is connected to a carrier 14 of a power split mechanism 10 described later. A clutch C1 is provided for connecting the sun gear 5 and the carrier 9 and for releasing the connection. In addition, a brake B1 is provided for connecting and fixing the sun gear 5 to a predetermined fixing portion such as a casing and releasing the fixing.

  The transmission unit 4 engages the clutch C1 to connect the sun gear 5 and the carrier 9 of the planetary gear mechanism. As a result, the entire transmission unit 4 rotates as a unit, and a so-called direct connection state (low speed stage) in which the speed increasing action and the speed reducing action are not generated is obtained. Then, by engaging the brake B1 in addition to the clutch C1, the entire transmission unit 4 is integrally fixed. As a result, the rotation of the carrier 14 and the engine 1 in the power split mechanism 10 is stopped. On the other hand, when only the brake B1 is engaged, the sun gear 5 in the transmission unit 4 is fixed. As a result, the carrier 9 that is the output member of the transmission unit 4 rotates at a higher speed than the ring gear 6 that is the input element and in the same direction as the ring gear 6. The transmission unit 4 functions as a speed increasing mechanism. That is, the transmission unit 4 sets a high speed (High).

  Provided on the output side of the transmission unit 4 is a power split mechanism 10 that splits and transmits the power transmitted from the engine 1 via the transmission unit 4 to the first motor / generator 2 side and the output side. Yes. The power split mechanism 10 is constituted by a differential mechanism having three rotating elements. In the example shown here, it is constituted by a single pinion type planetary gear mechanism. The planetary gear mechanism is disposed on the same axis as the engine 1, and the first motor / generator 2 is connected to the sun gear 11. The first motor / generator 2 is disposed adjacent to the power split mechanism 10 on the side opposite to the engine 1, and the rotor is connected to the sun gear 11. A ring gear 12 is disposed concentrically with the sun gear 11, and a pinion gear 13 meshing with the sun gear 11 and the ring gear 12 is held by a carrier 14 so that it can rotate and revolve. The carrier 14 is connected to the carrier 9 which is the output member of the transmission unit 4 described above. A drive gear 15 is connected to the ring gear 12. The drive gear 15 is disposed between the transmission unit 4 and the power split mechanism 10.

  A counter shaft 16 is arranged in parallel with the rotation center axis of the power split mechanism 10 and the first motor / generator 2, and a counter driven gear 17 meshing with the drive gear 15 is integrated with the counter shaft 16. It is attached to rotate.

  Further, the torque of the second motor / generator 3 is added to the torque transmitted from the power split mechanism 10 to the drive wheels 18. Specifically, the second motor / generator 3 is arranged in parallel with the counter shaft 16, and the reduction gear 19 connected to the rotor meshes with the counter driven gear 17. The reduction gear 19 is smaller in diameter than the counter driven gear 17, and is thus configured to amplify the torque of the second motor / generator 3 and transmit it to the counter driven gear 17 or the counter shaft 16.

  The counter shaft 16 is further provided with a differential drive gear 20 that rotates integrally therewith. The differential drive gear 20 meshes with a ring gear 22 in a differential gear 21 that is a final reduction gear. In FIG. 3, for the sake of drawing, the position of the differential gear 21 is shifted to the right side in FIG.

  Even in the vehicle including the power train shown in FIG. 3, each motor / generator 2, 3 is connected to the power storage device via a controller such as an inverter (not shown). These motor generators 2 and 3 function as motors, and currents are controlled so as to function as generators. In addition, the throttle opening and ignition timing of the engine 1 are controlled, and further automatic stop and restart control are performed. These controls are configured to be executed by an electronic control device (not shown). The first motor / generator 2 described above corresponds to the motor in the present invention, the power split mechanism 10 corresponds to the differential device in the present invention, the drive gear 15 corresponds to the output gear in the present invention, the clutch C1 and The brake B1 corresponds to a plurality of engagement mechanisms in the present invention.

  FIG. 1 is an enlarged sectional view showing a part of an example of a power transmission device according to the present invention. A transmission case 23 corresponding to the casing in the present invention is disposed on the output side of the engine 1. The transmission case 23 is formed in a cylindrical shape, for example, and the opening on the engine 1 side is covered with a front cover 24. The front cover 24 is attached to the transmission case 23 by a plurality of bolts 25. Inside the space formed by the transmission case 23 and the front cover 24, the transmission unit 4, the power split mechanism 10, and the first motor / generator 2 are arranged in this order from the engine 1 side. A through hole 26 is formed in an inner portion of the front cover 24 in the radial direction, and a bearing 27 is attached to an inner peripheral portion of the through hole 26. The input shaft 28 of the transmission 4 described above is supported by the front cover 24 via a bearing 27. Although not shown in detail, the end of the input shaft 28 on the engine 1 side is connected to the output shaft 1a of the engine 1 described above so that power can be transmitted.

  A flange 29 is formed on the input shaft 28, and the ring gear 6 of the planetary gear mechanism constituting the transmission unit 4 is connected to the flange 29. Further, the outer diameter of the end portion on the power split mechanism 10 side of the input shaft 28 is larger than that of other portions so as to be inserted into the counterbore 31 formed in the intermediate shaft 30 that functions as the output shaft of the transmission unit 4. It is getting thinner. A bush 32 is provided between the counterbore 31 and the intermediate shaft 30 so that the shafts 28 and 30 can rotate relative to each other.

  The intermediate shaft 30 described above is disposed on the inner peripheral portion of the sun gear 5 of the transmission unit 4 so as to be rotatable relative to the input shaft 28 and the sun gear 5. Further, the intermediate shaft 30 and the carrier 9 of the transmission unit 4 are fitted by a spline 33 so as to be integrally rotatable. Further, the intermediate shaft 30 is provided in a needle bearing provided in an inner peripheral portion of a through hole 43 formed in a center support 42 described later, and in an inner peripheral portion of the rotor shaft 2 a of the first motor / generator 2. It is rotatably supported by a needle bearing.

  A clutch C1 that selectively connects the sun gear 5 and the carrier 9 is provided on the opposite side of the transmission unit 4 in the axial direction of the input shaft 28. The clutch C1 includes a clutch disk 34 and a clutch plate 35 for connecting the sun gear 5 and the carrier 9, a hydraulic actuator 36 for engaging the clutch disk 34 and the clutch plate 35, and the clutch disk. 34 and a return spring 37 for separating the clutch plate 35 from each other. A clutch disk 34 and a clutch plate 35 are disposed on the outer peripheral side of the hydraulic actuator 36 and the return spring 37. The clutch disk 34 is connected so as to rotate integrally with the carrier 9, and the clutch plate 35 is connected so as to rotate integrally with the sun gear 5.

  A brake B <b> 1 for selectively fixing the sun gear 5 described above to the transmission case 23, which is a fixing portion, is provided on the outer peripheral side of the transmission portion 4. The brake B1 includes a friction plate 38 and a mating friction plate 39 for fixing the sun gear 5 to the transmission case 23, a hydraulic actuator 40 for engaging the friction plates 38 and 39, and the friction plate 38. And a return spring 41 for separating the mating friction plate 39. The friction plate 38 is connected to the sun gear 5 so as to rotate integrally. That is, in the example shown in FIG. 1, the friction plate 38 is connected to the clutch plate 35 of the clutch C1 in the axial direction. The mating friction plate 39 is fixed to the center support 42. The hydraulic actuator 40 and the return spring 41 are provided on the center support 42 on the outer peripheral side of the clutch C1.

  The center support 42 is a member configured separately from the transmission case 23, and is attached to the inner side of the front cover 24 at the opening of the transmission case 23 by a bolt (not shown). A through hole 43 is formed in the center support 42 as with the front cover 24, and a needle bearing 44 is attached to the inner peripheral portion of the through hole 43. The intermediate shaft 30 described above is supported by the center support 42 via the needle bearing 44.

  A flange 45 is formed on the side of the intermediate shaft 30 opposite to the transmission unit 4 with the center support 42 interposed therebetween, and the carrier 14 of the planetary gear mechanism constituting the power split mechanism 10 is connected to the flange 45. Has been. Further, the end of the intermediate shaft 30 on the power split mechanism 10 side is formed to have a smaller diameter than other portions so as to be inserted into a counterbore 46 formed in the rotor shaft 2a of the first motor / generator 2. Yes. A needle bearing 47 is attached to the inner peripheral portion of a counterbore hole 46 formed in the rotor shaft 2a. The small-diameter end of the intermediate shaft 30 described above is supported on the rotor shaft 2 a of the first motor / generator 2 via the needle bearing 47. The small-diameter end of the intermediate shaft 30 described above is disposed on the inner peripheral portion of the sun gear 11 of the power split mechanism 10 so as to be rotatable relative to the sun gear 11. The rotor shaft 2a of the first motor / generator 2 and the sun gear 11 are fitted by a spline 48 so as to be integrally rotatable.

  Drive gear 15 is connected to ring gear 12 of power split mechanism 10 so as to rotate together. The end of the drive gear 15 on the side of the engine 1 in the axial direction of the intermediate shaft 30 is attached to the center support 42 via a bearing 49, and the end of the drive gear 15 on the side of the first motor / generator 2 supports the bearing 50. It is attached to the partition wall part 51 via.

  The partition wall 51 described above is integrally formed with the mission case 23 as shown in FIG. A through hole 52 is formed in the partition wall 51, and a bearing 53 is attached to the inner peripheral portion of the through hole 52. The rotor shaft 2a of the first motor / generator 2 is supported on the partition wall 51 by the bearing 53 described above.

  In the example shown here, an oil passage 54 that supplies engagement hydraulic pressure to the clutch C1 and an oil passage 55 that supplies engagement hydraulic pressure to the brake B1 are formed in the center support 42. These oil passages 54 and 55 can be formed, for example, by drilling the center support 42, and are adjusted to a predetermined pressure for controlling the clutch C1 and the brake B1 from the valve body side (not shown). Each hydraulic pressure is supplied.

  The assembly of the transmission 4, the power split mechanism 10, and the first motor / generator 2 in the power transmission device having the above configuration will be briefly described. For example, first, the stator of the first motor / generator 2 is attached to the transmission case 23. A bearing 53 is attached to the through hole 52 of the partition wall 51. A rotor is incorporated in the inner peripheral portion of the stator, and a rotor shaft 2 a integrated with the rotor is supported by the partition wall portion 51 via a bearing 53. Thereafter, the opening of the transmission case 23 opposite to the engine 1 is closed by the end cover. Next, the transmission unit 4 is assembled, and the transmission unit 4 is attached to the center support 42 together with the input shaft 28, the clutch C1, the brake B1, and the like to be in a subassembly state.

  A bearing 50 is attached to the partition wall 51 in the transmission case 23, and the power split mechanism 10 and the intermediate shaft 30 are attached to the transmission case 23 via the bearing 50. Next, the bearing 49 is attached to the power split mechanism 10. The above-described center support 42 in the sub-assembly state is connected to the transmission case 23 in which the power split mechanism 10 is assembled. Specifically, the drive gear 15 is supported by the center support 42 via the bearing 49, and the intermediate shaft 30 and the carrier 9 are fitted by the spline 33. The intermediate shaft 30 is supported inside the rotor shaft 2a via a needle bearing 47. Further, the rotor shaft 2 a and the sun gear 11 of the power split mechanism 10 are fitted by a spline 48. Thereafter, the transmission case 23 and the front cover 24 are connected by the bolt 25. The input shaft 28 may be assembled to the transmission unit 4 immediately before the front cover 24 is attached to the transmission case 23. In that case, the subassembly does not include the input shaft 28.

  Thus, in the power transmission device having the above-described configuration, the transmission case starts from the member disposed on the side opposite to the engine 1, that is, in order of the first motor / generator 2, the power split mechanism 10, the clutch C 1 and the brake B 1, and the transmission unit 4. 23 can be assembled. In the power transmission device according to the present invention, the transmission unit 4, the brake B <b> 1, and the clutch C <b> 1 can be assembled in advance to the center support 42. That is, the transmission unit 4 can be a sub-assembly. Therefore, the subassembly can be attached to the transmission case 23 that houses the power split mechanism 10 and the first motor / generator 2. Thereby, in particular, the transmission unit 4 having a large number of parts can be easily connected to the first motor / generator 2. Therefore, in the power transmission device according to the present invention, as described above, the transmission unit 4, the power split mechanism 10, the first motor / generator 2, and the like can be easily assembled to the transmission case 23, and the workability thereof is good. become. This also makes it possible to improve the productivity of the power transmission device according to the present invention.

  In the power transmission device according to the present invention, as described above, the clutch C1 is disposed on the opposite side of the engine 1 across the transmission unit 4 in the axial direction, and the brake B1 is disposed on the outer peripheral side of the transmission unit 4. Has been placed. Specifically, the friction plate 38 and the counterpart friction plate 39 of the brake B1 are disposed on the outer peripheral side of the transmission unit 4, and the hydraulic actuator 40 is disposed on the outer peripheral side of the clutch C1. Since the friction plates 38 and 39 and the hydraulic actuator 40 are displaced in the axial direction as described above, the brake B1 can be effectively utilized by utilizing the space on the outer peripheral side of the clutch C1 and the space on the outer peripheral side of the transmission unit 4. The outer diameter can be reduced.

  FIG. 2 is a view for explaining the position of the differential gear in an example of the power transmission device according to the present invention. The opening of the transmission case 23 opposite to the engine 1 is closed by an end cover 56 as shown in FIG. The end cover 56 is attached to the transmission case 23 by bolts 57. An oil pump 58 is disposed inside the end cover 56 on the opposite side of the engine 1 across the first motor / generator 2. As shown in FIG. 2, the pump shaft 58a of the oil pump 58 is fitted to the intermediate shaft 30 by a spline, and the pump shaft and the rotor shaft 2a are configured to be relatively rotatable.

  As described above, the counter shaft 16 is disposed in parallel with the rotation axis of the intermediate shaft 30 and the rotor shaft 2a of the first motor / generator 2, and the counter driven gear 17 meshing with the drive gear 15 is provided. Are attached to the countershaft 16 so as to rotate together. Further, the second motor / generator 3 is arranged in parallel with the counter shaft 16, and a reduction gear 19 connected to the rotor shaft 3 a is engaged with the counter driven gear 17. The counter shaft 16 is further provided with a differential drive gear 20 that rotates integrally therewith. The differential drive gear 20 meshes with a ring gear 22 in a differential gear 21 that is a final reduction gear. In FIG. 2, for the sake of drawing, the position of the differential gear 21 is shifted downward in FIG.

  In the power transmission device having the above-described configuration, as shown in FIG. 2, the transmission unit 4 is disposed on the engine 1 side. Therefore, as compared with the case where the transmission unit 4 is not disposed on the engine 1 side, the drive gear 15 is located on the left side in FIG. 2, that is, in the axial direction of the power transmission device, as the transmission unit 4 is disposed on the engine 1 side. Located away from the engine 1. As a result, the counter driven gear 17 that meshes with the drive gear 15 is also arranged away from the engine 1 in the axial direction described above. In the example shown in FIG. 2, a differential drive gear 20 is provided closer to the engine 1 than the counter driven gear 17 in the axial direction. As a result, the differential gear 21 can be disposed near the center in the vehicle width direction.

  DESCRIPTION OF SYMBOLS 1 ... Engine (ENG), 1a ... Output shaft, 2 ... 1st motor generator (motor), 4 ... Transmission part, 10 ... Power split mechanism (differential device), 15 ... Drive gear (output gear), 23 ... Transmission case 24 ... Front cover 42 ... Center support 51 ... Bulkhead 56 ... End cover C1 ... Clutch B1 ... Brake

Claims (3)

An engine, a transmission unit connected to the engine and having a transmission ratio set according to the engagement and disengagement states of the plurality of engagement mechanisms, the transmission unit and the motor are connected, and torque is output from the output gear A power transmission device comprising: a differential device, wherein the transmission, the differential device, and the motor are housed in a casing;
The casing opens to the engine side and a partition wall is formed inside,
The motor is disposed on the same axis as the output shaft of the engine on the opposite side of the engine with the partition wall in between.
A center support separate from the casing is attached to the engine side of the partition in the casing.
The differential is disposed between the partition wall and the center support and on the same axis as the output shaft,
The speed change part is disposed on the same side as the output shaft on the engine side of the center support,
The output gear is rotatably supported by the partition wall and the center support. The transmission unit is constituted by a double pinion type planetary gear mechanism,
The engagement mechanism includes a clutch that selectively connects a sun gear and a carrier of the planetary gear mechanism, and a brake that selectively fixes the sun gear,
The center support is formed with an oil passage for supplying hydraulic pressure for engaging the clutch and another oil passage for supplying hydraulic pressure for engaging the brake. The power transmission device according to claim 1.   The power transmission device according to claim 2, wherein the brake is disposed on an outer peripheral side of the transmission unit in a radial direction of the output shaft.

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