JP5820904B2 - Support structure of planetary gear mechanism - Google Patents

Description

  The present invention relates to a support structure for a planetary gear mechanism that is provided in a case and includes a sun gear, a ring gear, and a planetary carrier that rotatably supports a plurality of planetary gears meshed with the sun gear and the ring gear. .

  In Patent Document 1, as shown in FIG. 6, a planetary gear mechanism 112A is provided as a speed reducer on a power transmission path between a left rear wheel (not shown) and an electric motor 102A that drives the left rear wheel. There is disclosed a vehicle drive device in which a planetary gear mechanism 112B is provided as a transmission on a power transmission path between a rear wheel (not shown) and an electric motor 102B that drives the right rear wheel.

  Further, in Patent Document 2, as shown in FIG. 7, a planetary gear mechanism 212 is provided as a speed reducer on a power transmission path between the electric motor 202 and wheels (not shown). Is transmitted from the rotor rotation shaft 207 and the sun gear 221 to the large-diameter pinion portion 226 meshing with the rotor rotation shaft 207 and the small-diameter pinion 227 integrated therewith, and the small-diameter pinion 227 rolls along the inner circumference of the fixed ring gear 224. It is described that deceleration rotation can be transmitted from the planetary carrier 223 to the wheel via the output shaft 210.

JP 2010-235051 A JP 2008-037355 A

  In the planetary gear mechanisms 112A and 112B described in Patent Document 1, one end side of each planetary carrier 123A and 123B is supported by the case 111 with bearings 133A and 133B, but the sprag of the one-way clutch 150 is provided on the other end side. Since 153 is disposed and not supported by the case 111, when a load is applied to the planetary carriers 123A and 123B, an axis shift occurs, and the planetary carriers 123A and 123B may be inclined with respect to the rotation axis. was there.

  In the planetary gear mechanism 212 described in Patent Document 2, one end side of the planetary carrier 223 is supported by a double row bearing 234, and the other end side is supported by another rotor bearing 233 via a rotor rotation shaft 207. . Therefore, a space for arranging the bearings on both the one side and the other side of the planetary gear 222 is required.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a support structure for a planetary gear mechanism that can secure a space in either one of the planetary gears while suppressing the axis shift of the planetary carrier. And

In order to achieve the above object, the invention described in claim 1
A sun gear (for example, sun gears 21A and 21B in the embodiment described later), a ring gear (for example, ring gears 24A and 24B in the embodiment described later), and a plurality of planetary gears meshed with the sun gear and the ring gear (for example, implementation described later) A planetary carrier (for example, planetary carriers 23A, 23B in the embodiment described later) that rotatably supports the planetary gears 22A, 22B) in the same axis, and a case (for example, case 11 in the embodiment described later). A support structure for a planetary gear mechanism (e.g., first and second planetary gear speed reducers 12A and 12B in the embodiments described later) disposed therein,
The planetary carrier extends in the axial direction, and supports a rotating shaft (for example, a pinion shaft 230 in an embodiment described later) that rotatably supports the planetary gear, and extends in the radial direction to hold the rotating shaft. An arm (for example, an inner arm 231 in an embodiment described later),
The planetary carrier includes a first bearing that supports one end of the rotating shaft in the radial direction (for example, bearings 33A and 33B in the embodiments described later) and a second bearing that supports the other end of the rotating shaft in the radial direction. It is supported in a radial direction with respect to the case by bearings (for example, bearings 19A and 19B and bearings 34A and 34B in embodiments described later),
The first and second bearings are disposed on one side of the planetary gear in the axial direction (for example, the axially outer side of an embodiment described later),
The other side of the planetary gear in the axial direction (for example, the inner side in the axial direction of the embodiment described later) is not provided with a bearing that supports the planetary carrier in the radial direction with respect to the case,
The second bearing is a bearing that supports other rotating shafts that rotate integrally with the sun gear (for example, cylindrical shafts 16A and 16B in embodiments described later) in a radial direction with respect to the case. Support the other end side of the rotating shaft via the rotating shaft,
The planetary gear includes a large-diameter gear (for example, first pinions 26A and 26B in an embodiment described later) and a small-diameter gear (for example, second pinions 27A and 27B in an embodiment described later) in the axial direction. Are two-stage pinion gears arranged in this order from one end side of the
The sun gear meshes with the large-diameter gear,
The ring gear meshes with the small diameter gear,
The other rotating shaft extends to the other end side of the rotating shaft from the sun gear and extends in the axial direction with the small-diameter gear (for example, extending portions 13A and 13B in the embodiments described later). )
The arm portion extends so as to overlap the extension portion in the axial direction (for example, a carrier base 231b in an embodiment described later), and is supported by the extension portion.

Moreover, in addition to the structure of Claim 1, the invention of Claim 2 is
The ring gear is supported in the radial direction by the second bearing through the planetary carrier.

In addition to the configuration described in claim 1 or 2, the invention described in claim 3
The case includes a wall portion extending in the radial direction on one side of the planetary gear (for example, partition walls 18A and 18B in embodiments described later),
The wall portion is provided with the first and second bearings.

Moreover, in addition to the structure of any one of Claims 1-3, invention of Claim 4 is provided.
The planetary gear mechanism includes a vehicle drive source (for example, first and second electric motors 2A and 2B in embodiments described later) and wheels (for example, a left rear wheel LWr and a right rear wheel RWr in embodiments described later). Arranged on the power transmission path,
The other rotation shaft is a power transmission shaft (for example, cylindrical shafts 16A and 16B in the embodiments described later) that connects the drive source and the planetary gear mechanism,
The planetary carrier is connected to the wheels by other power transmission shafts (for example, axles 10A and 10B in embodiments described later),
The power transmission shaft has a hollow structure;
The other power transmission shaft is inserted into the power transmission shaft,
The drive source and the wheel are arranged on one side in the axial direction with respect to the planetary gear mechanism.

Moreover, in addition to the structure of Claim 4, the invention of Claim 5 adds to the structure of Claim 4,
The other power transmission shaft is supported in a radial direction with respect to the case by a third bearing (for example, bearings 20A and 20B in embodiments described later),
The third bearing is disposed on one side of the planetary gear in the axial direction;
The other side of the planetary gear in the axial direction is not provided with a bearing for supporting the other power transmission shaft in the radial direction with respect to the case.

Moreover, in addition to the structure of any one of Claims 1-5, the invention of Claim 6 is
One of the sun gear, the planetary carrier, and the ring gear of the planetary gear mechanism is provided with one-way power transmission means (for example, one-way clutch 50 in the embodiment described later) or power connection / disconnection means (for example, implementation described later). In the form of a hydraulic brake 60),
The one-way power transmission means or power connection / disconnection means is arranged on the other side of the planetary gear in the axial direction.

Moreover, in addition to the structure of any one of Claims 1-6, invention of Claim 7 is provided,
The planetary gear mechanism includes two planetary gear mechanisms arranged in mirror symmetry adjacent to each other,
The case is characterized in that a bearing for supporting each planetary carrier in the radial direction is not provided between the two planetary gear mechanisms.

According to the first aspect of the present invention, since the first and second bearings that support both ends of the planetary carrier are concentrated on one side of the planetary gear, the other side of the planetary gear is suppressed while suppressing the axis shift of the planetary carrier. Space can be secured.
In addition, the second bearing supports the other end side of the rotating shaft via another rotating shaft that rotates integrally with the sun gear, so that the bearing for supporting the planetary carrier and the other rotating shaft is made common. Thus, the number of parts can be reduced and the support structure of the planetary gear mechanism can be reduced in size.

  In addition, by adopting a two-stage pinion gear as a planetary gear, it is possible to set a desired gear ratio while suppressing an increase in the radial direction, and an extension portion is formed in a dead space formed inside the small diameter gear in the radial direction. By disposing and supporting the arm portion, it is possible to more stably support the planetary carrier while suppressing the planetary carrier from being elongated in the axial direction.

  According to the invention described in claim 2, it is not necessary to separately provide a bearing for supporting the ring gear in the case.

  According to the third aspect of the present invention, since only one wall portion is required to support the first and second bearings, the planetary gear mechanism support structure can be reduced in size as compared with the case where the first and second bearings are separately formed. .

  According to the fourth aspect of the present invention, the two power transmission shafts can be arranged on the same axis, and the radial size can be reduced. Moreover, the axial lengthening can be suppressed by concentrating the driving source and the wheel on one side of the planetary gear mechanism.

  According to the fifth aspect of the invention, in addition to the bearing that supports the planetary carrier, the third bearing that supports the other power transmission shaft is also concentrated on one side of the planetary gear. Space can be secured.

  According to the sixth aspect of the present invention, since the one-way power transmission means or the power connection / disconnection means can be provided in the vicinity of the rotation axis on the other side of the planetary gear, the radial direction can be reduced.

  According to the seventh aspect of the present invention, it is possible to secure a larger space by forming the two spaces on the side opposite to the side where the first and second bearings are disposed.

1 is a block diagram showing a schematic configuration of a hybrid vehicle that is an embodiment of a vehicle on which a support structure for a planetary gear mechanism according to the present invention can be mounted. It is a longitudinal cross-sectional view of a rear-wheel drive device. FIG. 3 is an enlarged cross-sectional view of an upper portion of the rear wheel drive device shown in FIG. 2. FIG. 3 is an enlarged cross-sectional view of a left side portion of the rear wheel drive device shown in FIG. 2 when a vertically downward force acts on the planetary carrier. FIG. 3 is an enlarged cross-sectional view of a left side portion of the rear wheel drive device shown in FIG. 2 when a vertical upward load is applied to the planetary carrier. 1 is a longitudinal sectional view of a vehicle drive device described in Patent Document 1. FIG. 5 is a longitudinal sectional view of a vehicle drive device described in Patent Document 2. FIG.

The vehicle drive device on which the planetary gear mechanism support structure according to the present invention is mounted is used, for example, in a vehicle having a drive system as shown in FIG. In the following description, the case where the vehicle drive device is used for rear wheel drive will be described as an example, but it may be used for front wheel drive.
A vehicle 3 shown in FIG. 1 is a hybrid vehicle having a drive device 6 (hereinafter referred to as a front wheel drive device) in which an internal combustion engine 4 and an electric motor 5 are connected in series at the front portion of the vehicle. Is transmitted to the front wheels Wf via the transmission 7, while the power of the driving device 1 (hereinafter referred to as a rear wheel driving device) provided at the rear of the vehicle separately from the front wheel driving device 6 is the rear wheel Wr. (RWr, LWr). The electric motor 5 of the front wheel drive device 6 and the first and second electric motors 2A and 2B of the rear wheel drive device 1 on the rear wheel Wr side are connected to the battery 9, and supply power from the battery 9 and energy to the battery 9 Regeneration is possible. In FIG. 1, reference numeral 8 denotes a control device for controlling the entire vehicle.

First, a vehicle drive device according to an embodiment equipped with a planetary gear mechanism support mechanism according to the present invention will be described with reference to FIGS. 2 and 3.
FIG. 2 is a longitudinal sectional view of the entire rear wheel drive device 1, and FIG. 3 is an enlarged partial sectional view of the upper part of FIG. In the figure, reference numeral 11 denotes a case of the rear wheel drive device 1, and the case 11 is arranged on the left and right sides of the central case 11 </ b> M so as to sandwich the central case 11 </ b> M and the central case 11 </ b> M. It is comprised from the side cases 11A and 11B arrange | positioned, and the whole is formed in a substantially cylindrical shape. Inside the case 11, there are axles 10A, 10B for the rear wheels Wr, first and second motors 2A, 2B for driving the axles, and first and second motors for decelerating the drive rotation of both the motors 2A, 2B. Planetary gear type speed reducers 12A and 12B are arranged side by side on the same axis. The axle 10A, the first electric motor 2A and the first planetary gear speed reducer 12A drive and control the left rear wheel LWr, and the axle 10B, the second electric motor 2B and the second planetary gear speed reducer 12B drive the right rear wheel RWr. Control. The axle 10A, the first electric motor 2A and the first planetary gear speed reducer 12A, and the axle 10B, the second electric motor 2B and the second planetary gear speed reducer 12B are arranged symmetrically in the vehicle width direction in the case 11. ing. The left rear wheel LWr is positioned opposite to the first planetary gear type reduction gear 12A with respect to the first electric motor 2A, and the right rear wheel RWr is also connected to the second planetary gear type reduction gear 12B with respect to the second electric motor 2B. Located on the opposite side.

  The side cases 11A and 11B are respectively provided with partition walls 18A and 18B extending radially inward on the central case 11M side. Between the side cases 11A and 11B and the partition walls 18A and 18B, first and first partitions are provided. Two electric motors 2A and 2B are arranged. Further, first and second planetary gear speed reducers 12A and 12B are arranged in a space surrounded by the central case 11M and the partition walls 18A and 18B. The arrows in FIGS. 2 and 3 indicate the positional relationship when the rear wheel drive device 1 is mounted on the vehicle.

  The rear wheel drive device 1 is provided with a breather device 40 that communicates the inside and outside of the case 11 so that the air inside the case 11 escapes to the outside through the breather chamber 41 so that the air does not become excessively high temperature and pressure. Configured as follows. The breather chamber 41 is disposed at the upper part in the vertical direction of the case 11, and includes an outer wall of the central case 11M, a first cylindrical wall 43 extending substantially horizontally in the central case 11M on the left side case 11A side, and a right side case. A second cylindrical wall 44 extending substantially horizontally on the 11B side, a left and right dividing wall 45 connecting the inner ends of the first and second cylindrical walls 43, 44, and a left side case 11A of the first cylindrical wall 43. A space formed by a baffle plate 47A attached so as to abut on the side tip, and a baffle plate 47B attached so as to abut on the right side case 11B side tip of the second cylindrical wall 44. The

  The first and second cylindrical walls 43, 44 and the left and right dividing walls 45 that form the lower surface of the breather chamber 41 are such that the first cylindrical wall 43 is positioned radially inward from the second cylindrical wall 44, and the left and right dividing walls 45 are A third cylinder that extends from the inner end of the second cylindrical wall 44 to the inner end of the first cylindrical wall 43 while being bent while reducing the diameter, and further extends radially inward and extends substantially horizontally. Reach wall 46. The third cylindrical wall 46 is located on the inner side of both outer end portions of the first cylindrical wall 43 and the second cylindrical wall 44 and substantially in the center thereof.

  In the central case 11M, baffle plates 47A and 47B are provided in the space between the first cylindrical wall 43 and the outer wall of the central case 11M or the space between the second cylindrical wall 44 and the outer wall of the central case 11M as the first planet. It is fixed so as to be separated from the gear type speed reducer 12A or the second planetary gear type speed reducer 12B. In addition, an external communication path 49 that connects the breather chamber 41 and the outside is connected to the central case 11M on the upper surface in the vertical direction of the breather chamber 41.

  In the first and second electric motors 2A and 2B, stators 14A and 14B are fixed to side cases 11A and 11B, respectively, and annular rotors 15A and 15B are rotatably arranged on the inner peripheral sides of the stators 14A and 14B. Yes. Cylindrical shafts 16A and 16B surrounding the outer periphery of the axles 10A and 10B are coupled to the inner peripheral portions of the rotors 15A and 15B, and the cylindrical shafts 16A and 16B can be relatively rotated coaxially with the axles 10A and 10B. The side cases 11A and 11B are supported in the radial direction by bearings 19A and 19B and bearings 34A and 34B on the end walls 17A and 17B and the partition walls 18A and 18B, respectively. Sun gears 21A and 21B of first and second planetary gear speed reducers 12A and 12B, which will be described later, are integrally formed on the inner side in the axial direction of the cylindrical shafts 16A and 16B, and extend further inward in the axial direction than the sun gears 21A and 21B. Outlet portions 13A and 13B are formed. Further, on the outer side in the axial direction of the bearings 19A and 19B that support the cylindrical shafts 16A and 16B, bearings 20A and 20B that support the axles 10A and 10B in the radial direction with respect to the end walls 17A and 17B of the side cases 11A and 11B. The bearings for supporting the axles 10A and 10B are not provided inside the axles 10A and 10B in the axial direction.

  The first and second electric motors 2A and 2B including the stators 14A and 14B and the rotors 15A and 15B have the same radius, and the first and second electric motors 2A and 2B are arranged in mirror symmetry with each other. The axle 10A and the cylindrical shaft 16A pass through the first electric motor 2A and extend from both ends of the first electric motor 2A. The axle 10B and the cylindrical shaft 16B also penetrate the second electric motor 2B. , Extending from both ends of the second electric motor 2B.

  The first and second planetary gear speed reducers 12A and 12B include sun gears 21A and 21B and planetary carriers 23A and 23B that rotatably support a plurality of planetary gears 22A and 22B meshed with the sun gears 21A and 21B. Ring gears 24A and 24B meshed with the outer peripheral sides of the planetary gears 22A and 22B are provided on the same axis, and the driving forces of the first and second electric motors 2A and 2B are input to the sun gears 21A and 21B, respectively, and are decelerated. Driving force is output to the axles 10A and 10B through the planetary carriers 23A and 23B. The first and second planetary gear type speed reducers 12A and 12B have the same axial center as the axles 10A and 10B and the cylindrical shafts 16A and 16B, and the axial direction coincides with the axial direction.

  The sun gears 21A and 21B are formed integrally with the cylindrical shafts 16A and 16B. The planetary gears 22A and 22B are double pinions having first pinions 26A and 26B having large diameters directly meshed with the sun gears 21A and 21B, and second pinions 27A and 27B having smaller diameters than the first pinions 26A and 26B. The first pinions 26A and 26B and the second pinions 27A and 27B are integrally formed in a state of being coaxially offset in the axial direction. The second pinions 27A and 27B are arranged at positions that overlap the extending portions 13A and 13B of the cylindrical shafts 16A and 16B in the axial direction. The planetary gears 22A and 22B are supported by the pinion shaft 230 of the planetary carriers 23A and 23B via needle bearings 31A and 31B.

  In the planetary carriers 23 </ b> A and 23 </ b> B, the inner end portion of the pinion shaft 230 extending in the axial direction is held by the inner arm portion 231. The inner arm portion 231 includes a carrier plate 231a that extends in the radial direction, and a carrier base 231b that is integrally attached to the inner diameter side of the carrier plate 231a and is spline-fitted to the axles 10A and 10B so as to be integrally rotatable. The The carrier base 231b extends to the extending portions 13A and 13B so as to overlap the extending portions 13A and 13B of the cylindrical shafts 16A and 16B in the axial direction, and bearings 71A and 71B are attached to the extending portions 13A and 13B. Supported through. Further, the carrier base 231b extends to the opposite side to the extending portions 13A and 13B so as to overlap with small diameter portions 29A and 29B of ring gears 24A and 24B described later in the axial direction.

  On the other hand, the outer end of the pinion shaft 230 is supported by the outer arm 232 in the radial direction on the partition walls 18A and 18B via the bearings 33A and 33B.

  The ring gears 24A and 24B have gear portions 28A and 28B that are meshed with the second pinions 27A and 27B whose inner peripheral surfaces are small diameters, and small diameters that are smaller than the gear portions 28A and 28B and that are opposed to each other at an intermediate position of the case 11. Parts 29A, 29B, and connecting parts 30A, 30B for connecting the axially inner ends of the gear parts 28A, 28B and the axially outer ends of the small diameter parts 29A, 29B in the radial direction.

  The gear portions 28A and 28B face each other in the axial direction with a third cylindrical wall 46 formed at the inner diameter side end portion of the left and right dividing wall 45 of the central case 11M. The outer diameter surfaces of the small diameter portions 29A and 29B are spline-fitted to an inner race 51 of a one-way clutch 50, which will be described later, and the ring gears 24A and 24B are connected to each other so as to rotate integrally with the inner race 51 of the one-way clutch 50. Configured. Further, the inner peripheral surfaces of the small diameter portions 29A and 29B are supported on the carrier base 231b so as to be relatively rotatable via bearings 72A and 72B. The bearings 73A and 73B are also arranged between the coupling portions 30A and 30B and the carrier plate 231a.

  On the second planetary gear type speed reducer 12B side, between the second cylindrical wall 44 of the central case 11M constituting the case 11 and the gear portion 28B of the ring gear 24B, a hydraulic brake constituting braking means for the ring gear 24B 60 is arranged so as to overlap with the first pinion 26B in the radial direction and overlap with the second pinion 27B in the axial direction. The hydraulic brake 60 includes a plurality of fixed plates 35 that are spline-fitted to the inner peripheral surface of the second cylindrical wall 44 and a plurality of rotary plates 36 that are spline-fitted to the outer peripheral surface of the gear portion 28B of the ring gear 24B. The plates 35 and 36 are arranged alternately in the directions, and are fastened and released by an annular piston 37. The piston 37 is accommodated in an annular cylinder chamber formed between the left and right dividing walls 45 of the central case 11M and the third cylindrical wall 46, and is further provided with a receiving provided on the outer peripheral surface of the third cylindrical wall 46. The elastic member 39 supported by the seat 38 is constantly urged in a direction to release the fixed plate 35 and the rotating plate 36.

  More specifically, the working chamber S into which oil is directly introduced is defined between the left and right dividing walls 45 and the piston 37, and when the pressure of the oil introduced into the working chamber S exceeds the urging force of the elastic member 39, The piston 37 moves forward (to the right), and the fixed plate 35 and the rotating plate 36 are pressed against each other and fastened. When the urging force of the elastic member 39 exceeds the pressure of the oil introduced into the working chamber S, the piston 37 moves backward (leftward movement), and the fixed plate 35 and the rotating plate 36 are separated and released. . The hydraulic brake 60 is connected to an electric oil pump 70 (see FIG. 1).

  In the case of this hydraulic brake 60, the fixed plate 35 is supported by the second cylindrical wall 44 extending from the left and right dividing walls 45 of the central case 11M constituting the case 11, while the rotating plate 36 is supported by the gear portion 28B of the ring gear 24B. Therefore, when the plates 35 and 36 are pressed by the piston 37, a braking force is applied to the ring gear 24B by the frictional engagement between the plates 35 and 36, and is fixed. When the fastening by the piston 37 is released from this state, the ring gear 24B is allowed to rotate freely. As described above, since the ring gears 24A and 24B are connected to each other, the braking force is also applied to the ring gear 24A when the hydraulic brake 60 is fastened, and the ring gear 24A is fixed when the hydraulic brake 60 is released. Free rotation is allowed.

  Also, a space is secured between the coupling portions 30A and 30B of the ring gears 24A and 24B facing each other in the axial direction, and only power in one direction is transmitted to the ring gears 24A and 24B in the space to transmit power in the other direction. A one-way clutch 50 is arranged to be shut off. The one-way clutch 50 has a large number of sprags 53 interposed between an inner race 51 and an outer race 52. The inner race 51 is connected to the small diameter portions 29A, 29B of the ring gears 24A, 24B by spline fitting. It is configured to rotate integrally. The outer race 52 is positioned by the third cylindrical wall 46 and is prevented from rotating.

  The one-way clutch 50 is configured to engage and lock the rotation of the ring gears 24A and 24B when the vehicle 3 moves forward with the power of the first and second electric motors 2A and 2B. More specifically, the one-way clutch 50 is used when the rotational power in the forward direction on the first and second electric motors 2A, 2B side (rotational direction when the vehicle 3 moves forward) is input to the wheel Wr side. The engaged state is entered, and when the rotational power in the reverse direction on the first and second motors 2A, 2B side is input to the wheel Wr side, the disengaged state is established, and the forward rotational power on the wheel Wr side is the first. And when it is input to the second electric motors 2A and 2B, it is in the disengaged state, and when the rotational power in the reverse direction on the wheel Wr side is input to the first and second electric motors 2A and 2B, it is engaged. It becomes.

  Thus, in the rear wheel drive device 1 of the present embodiment, the one-way clutch 50 and the hydraulic brake 60 are provided in parallel on the power transmission path between the first and second electric motors 2A and 2B and the wheel Wr. The hydraulic brake 60 is controlled to a released state and an engaged state by the pressure of oil supplied from the oil pump 70 according to the traveling state of the vehicle and the engaged / disengaged state of the one-way clutch 50. For example, when the vehicle 3 moves forward by powering driving of at least the first and second electric motors 2A and 2B (for example, rear wheel driving or four wheel driving) such as when the vehicle starts, power transmission is performed because the one-way clutch 50 is engaged. In order to be in a possible state, the hydraulic brake 60 is typically controlled to be in a released state. When the vehicle 3 moves forward by driving the internal combustion engine 4 and / or the electric motor 5 (front wheel drive) and exceeds the motor speed limit, the one-way clutch 50 is disengaged and the hydraulic brake is released. By controlling to the state, over-rotation of the first and second electric motors 2A and 2B is prevented. On the other hand, when the vehicle 3 moves backward or regenerates, the one-way clutch 50 is disengaged, so the hydraulic brake 60 is controlled to be in the engaged state, so that the reverse direction from the first and second electric motors 2A, 2B side is achieved. Rotational power is output to the wheel Wr side, or forward rotational power on the wheel Wr side is input to the first and second electric motors 2A and 2B.

The support structure for the first and second planetary gear speed reducers 12A and 12B in the rear wheel drive device 1 configured as described above will be described in detail below.
The sun gears 21A, 21B have cylindrical walls 16A, 16B formed integrally with end walls 17A, 17B and partition walls 18A located on both sides of the motors 2A, 2B via bearings 19A, 19B and bearings 34A, 34B. By being supported by 18B in the radial direction, it is supported in the radial direction by the end walls 17A and 17B and the partition walls 18A and 18B via the bearings 19A and 19B and the bearings 34A and 34B. The ring gears 24A and 24B are supported in the radial direction so that the inner peripheral surfaces of the small diameter portions 29A and 29B can be relatively rotated by the carrier base 231b via the bearings 72A and 72B.

  In the planetary carriers 23A and 23B that support the ring gears 24A and 24B via the carrier base 231b, the axially outer side of the pinion shaft 230 is radially supported by the partition walls 18A and 18B by the bearings 33A and 33B via the outer arm portion 232. The inner side (carrier base 231b) of the pinion shaft 230 extends from the cylindrical shafts 16A and 16B supported by the end walls 17A and 17B and the partition walls 18A and 18B via the bearings 19A and 19B and the bearings 34A and 34B. The protruding portions 13A and 13B are supported in the radial direction via bearings 71A and 71B. That is, the planetary carriers 23A and 23B are supported on the case 11 in the radial direction on both sides of the pinion shaft 230 via the bearings 33A and 33B, the bearings 19A and 19B, and the bearings 34A and 34B.

  The bearings 33A and 33B, the bearings 19A and 19B, and the bearings 34A and 34B are all arranged on the outer side in the axial direction of the planetary gears 22A and 22B. The bearing which supports 23B is not provided. In addition, although the bearings 19A and 19B and the bearings 34A and 34B are provided as bearings that support the inner sides in the axial direction of the planetary carriers 23A and 23B, any one of them may be provided. As described above, since at least two bearings supporting the outside in the axial direction and the inside in the axial direction of the planetary carriers 23A and 23B are concentrated on the outside in the axial direction of the planetary gears 22A and 22B, a space is formed inside the planetary gears 22A and 22B in the axial direction. Can be secured.

  In the rear wheel drive device 1 of the above-described embodiment, the one-way clutch 50 is disposed between the two planetary gear mechanisms, that is, on the inner side in the axial direction of the first and second planetary gear speed reducers 12A and 12B. By arranging the one-way clutch 50 in the space formed inside the first and second planetary gear speed reducers 12A and 12B, it is possible to reduce the size in the radial direction.

4 is an enlarged cross-sectional view of the left side portion of the rear wheel drive device shown in FIG. 2 when a load in the vertical direction acts on the planetary carrier, and FIG. 5 shows a case in which a load in the vertical direction acts on the planetary carrier. FIG. 3 is an enlarged cross-sectional view of a left side portion of the rear wheel drive device shown in FIG. 2.
As shown in FIGS. 4 and 5, when a load below or above the vertical direction acts on the planetary carriers 23A and 23B, the outer side of the pinion shaft 230 is a bearing 33A, as shown by the white arrow in the figure. 33B is supported in the radial direction by the partition walls 18A and 18B, and the inner side of the pinion shaft 230 is supported in the radial direction by the partition walls 18A and 18B through the bearings 34A and 34B, and the end wall through the bearings 19A and 19B. 17A and 17B are supported in the radial direction. Therefore, according to the present embodiment, the planetary carriers 23A and 23B are supported by the case 11 in the radial direction at both ends of the pinion shaft 230. Therefore, even when a load is applied, the occurrence of axial misalignment is suppressed.

  As described above, according to the present embodiment, the planetary carriers 23A and 23B include the bearings 33A and 33B that radially support the axially outer side of the pinion shaft 230 and the axially inner side of the pinion shaft 230 in the radial direction. The bearings 19A and 19B and the bearings 34A and 34B are supported by the case 11 in the radial direction. The bearings 33A and 33B, the bearings 19A and 19B, and the bearings 34A and 34B are disposed on the outer side in the axial direction of the planetary gears 22A and 22B. Since the planetary gears 22A and 22B are not provided with bearings for supporting the planetary carriers 23A and 23B in the radial direction with respect to the case 11 inside the planetary gears 22A and 22B, the planetary gears 22A and 22B are restrained from being displaced. , 22B can be secured on the inner side in the axial direction.

  Further, the bearings 19A, 19B and the bearings 34A, 34B are bearings that support the cylindrical shafts 16A, 16B that rotate integrally with the sun gears 21A, 21B in the radial direction, and the pinion shaft 230 via the cylindrical shafts 16A, 16B. Since the bearings for supporting the planetary carriers 23A, 23B and the cylindrical shafts 16A, 16B can be shared, the number of parts can be reduced and the planetary gear speed reducers 12A, 12B can be reduced. The support structure can be reduced in size.

  The cylindrical shafts 16A and 16B include extending portions 13A and 13B extending inward in the axial direction of the pinion shaft 230 relative to the sun gears 21A and 21B. The bearings 19A and 19B and the bearings 34A and 34B include the extending portions 13A and 13B. Since the inner side of the pinion shaft 230 is supported via the shaft, the planetary carriers 23A and 23B are stably supported by increasing the axial width of the cylindrical shafts 16A and 16B that rotate integrally with the sun gears 21A and 21B. be able to.

  The planetary gears 22A and 22B are two-stage pinion gears in which large-diameter first pinions 26A and 26B and small-diameter second pinions 27A and 27B are connected in the axial direction, and the sun gears 21A and 21B are first pinions. 26A and 26B, the ring gears 24A and 24B mesh with the second pinions 27A and 27B, and the extending portions 13A and 13B and the second pinions 27A and 27B overlap in the axial direction. By arranging the extending portions 13A and 13B in the dead space, the planetary gears 22A and 22B can be prevented from being elongated in the axial direction.

  Further, since the ring gears 24A and 24B are radially supported by the bearings 19A and 19B and the bearings 34A and 34B through the planetary carriers 23A and 23B, a bearing for supporting the ring gears 24A and 24B is provided in the case 11 separately. There is no need.

  Further, the case 11 includes partition walls 18A and 18B extending radially in the axial direction outside of the planetary gears 22A and 22B. Since the bearings 33A and 33B and the bearings 34A and 34B are provided on the partition walls 18A and 18B, the bearings 33A and 34B are provided. Since only one wall portion is required to support the 33B and the bearings 34A and 34B, the support structure of the planetary gear type speed reducers 12A and 12B can be reduced in size compared to the case where they are formed separately.

  The planetary gear speed reducers 12A and 12B are disposed on the power transmission path between the first and second electric motors 2A and 2B and the rear wheel Wr as drive sources of the vehicle 3, respectively, and the first and second electric motors 2A, 2B and planetary gear type reduction gears 12A and 12B, and cylindrical shafts 16A and 16B, and planetary gear type reduction gears 12A and 12B and axles 10A and 10B connecting the rear wheels Wr. The cylindrical shafts 16A and 16B have a hollow structure, and the axles 10A and 10B are inserted into the cylindrical shafts 16A and 16B. The first electric motor 2A and the left rear wheel are axially outward with respect to the planetary gear type reduction gear 12A. LWr is arranged, and the second electric motor 2B and the right rear wheel RWr are arranged on the outer side in the axial direction with respect to the planetary gear type speed reducer 12B, so two power transmissions of the axles 10A and 10B and the cylindrical shafts 16A and 16B are provided. The shafts can be arranged on the same axis, and the radial size can be reduced. In addition, since the planetary gear type speed reducers 12A and 12B can be arranged adjacently between the first and second electric motors 2A and 2B, an increase in the axial direction can be suppressed.

  The case 11 includes bearings 20A and 20B that support the axles 10A and 10B in the radial direction. The bearings 20A and 20B are disposed on the outer side in the axial direction of the planetary gears 22A and 22B. The case 11 includes the planetary gears 22A and 22B. Since the bearings for supporting the axles 10A, 10B are not provided on the inner side in the axial direction, the bearings for supporting the axles 10A, 10B are concentrated outside the planetary gears 22A, 22B in addition to the bearings for supporting the planetary carriers 23A, 23B. Since it is arranged, a space can be secured on the inner side in the axial direction of the planetary gears 22A, 22B.

  Further, the one-way clutch 50 is connected to the ring gears 24A, 24B, and the one-way clutch 50 is disposed on the inner side in the axial direction of the planetary gears 22A, 22B. The one-way clutch 50 can be provided in the vicinity, and the size in the radial direction can be reduced. Instead of the one-way clutch 50, a hydraulic brake 60 may be provided. Furthermore, the one-way clutch 50 or the hydraulic brake 60 may be provided in the sun gears 21A and 21B, and the first and second electric motors 2A and 2B may be connected to the ring gears 24A and 24B.

  Further, the planetary gear mechanism includes two first and second planetary gear type speed reducers 12A and 12B that are arranged adjacent to each other in mirror symmetry, and the case 11 has two first and second planetary gear type speed reducers. Since the bearings for supporting the planetary carriers 23A and 23B in the radial direction are not provided between the machines 12A and 12B, the bearings 19A and 19B, the bearings 33A and 33B and the bearings 34A and 34B are opposite to the side where they are arranged. By forming two spaces on the side, a larger space can be secured.

In addition, this invention is not limited to embodiment mentioned above, A deformation | transformation, improvement, etc. are possible suitably.
Any planetary gear mechanism may be employed as long as it is a planetary gear mechanism disposed on a power transmission path between a vehicle drive source and wheels.
For example, the drive source may be an engine regardless of the electric motor, and may be incorporated in the front wheel drive device.

2A 1st electric motor (drive source)
2B Second electric motor (drive source)
10A, 10B Axle (other power transmission shaft)
12A, 12B First and second planetary gear type reduction gears (planetary gear mechanism)
13A, 13B Extension parts 16A, 16B Cylindrical shaft (other rotating shaft, power transmission shaft)
18A, 18B Bulkhead (wall)
20A, 20B bearing (third bearing)
21A, 21B Sun gear 22A, 22B Planetary gear 23A, 23B Planetary carrier 24A, 24B Ring gear 26A, 26B First pinion (large diameter gear)
27A, 27B Second pinion (small diameter gear)
33A, 33B Bearing (first bearing)
19A, 19B Bearing (second bearing)
34A, 34B Bearing (second bearing)
50 one-way clutch (one-way power transmission means)
60 Hydraulic brake (power connection / disconnection means)
230 Pinion shaft (rotating shaft)
231 Inner arm 232 Outer arm LWr Left rear wheel (wheel)
RWr Right rear wheel (wheel)

Claims (7)

A planetary gear mechanism support structure comprising a sun gear, a ring gear, and a planetary carrier that rotatably supports a plurality of planetary gears meshed with the sun gear and the ring gear on the same axis. ,
The planetary carrier includes a rotating shaft that extends in the axial direction and rotatably supports the planetary gear, and an arm that extends in the radial direction and holds the rotating shaft.
The planetary carrier is supported in a radial direction with respect to the case by a first bearing that supports one end of the rotating shaft in a radial direction and a second bearing that supports the other end of the rotating shaft in a radial direction. And
The first and second bearings are disposed on one side of the planetary gear in the axial direction,
The other side of the planetary gear in the axial direction is not provided with a bearing that supports the planetary carrier in the radial direction with respect to the case,
The second bearing is a bearing that supports another rotating shaft that rotates integrally with the sun gear in a radial direction with respect to the case, and supports the other end side of the rotating shaft via the other rotating shaft. And
The planetary gear is a two-stage pinion gear in which a large-diameter gear and a small-diameter gear are connected in this order from one end side of the rotating shaft in the axial direction.
The sun gear meshes with the large-diameter gear,
The ring gear meshes with the small diameter gear,
The other rotating shaft includes an extending portion that extends to the other end side of the rotating shaft from the sun gear and overlaps the small diameter gear in the axial direction.
The support structure for a planetary gear mechanism, wherein the arm portion extends so as to overlap the extension portion in the axial direction and is supported by the extension portion.   The planetary gear mechanism support structure according to claim 1, wherein the ring gear is supported in a radial direction by the second bearing through the planetary carrier. The case includes a wall portion extending in a radial direction on one side of the planetary gear,
The planetary gear mechanism support structure according to claim 1 or 2, wherein the wall portion is provided with the first and second bearings. The planetary gear mechanism is disposed on a power transmission path between a vehicle drive source and wheels,
The other rotating shaft is a power transmission shaft that connects the drive source and the planetary gear mechanism,
The planetary carrier is connected to the wheel by another power transmission shaft,
The power transmission shaft has a hollow structure;
The other power transmission shaft is inserted into the power transmission shaft,
The planetary gear mechanism support according to any one of claims 1 to 3, wherein the drive source and the wheel are arranged on one side in the axial direction with respect to the planetary gear mechanism. Construction. The other power transmission shaft is supported in a radial direction with respect to the case by a third bearing,
The third bearing is disposed on one side of the planetary gear in the axial direction;
5. The planetary gear mechanism support according to claim 4, wherein a bearing for supporting the other power transmission shaft in a radial direction with respect to the case is not provided on the other side of the planetary gear in the axial direction. Construction. One-way power transmission means or power connection / disconnection means is connected to either the sun gear, the planetary carrier, or the ring gear of the planetary gear mechanism,
The planetary gear mechanism support according to any one of claims 1 to 5, wherein the one-way power transmission unit or the power connection / disconnection unit is disposed on the other side of the planetary gear in the axial direction. Construction. The planetary gear mechanism includes two planetary gear mechanisms arranged in mirror symmetry adjacent to each other,
The planetary gear mechanism according to any one of claims 1 to 6, wherein the case does not include a bearing that supports each planetary carrier in a radial direction between the two planetary gear mechanisms. Support structure.

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