JP6705345B2 - Vehicle power transmission device support structure - Google Patents

Description

The present invention relates to a support structure for a power transmission device for a vehicle.

Conventionally, a cylindrical gear member having a gear on the outer peripheral side is used as a supporting member in a rolling bearing including an outer ring internally fitted to the inner peripheral surface of the gear member and an inner ring externally fitted to the outer peripheral surface of the support member. There is known a power transmission device for a vehicle which is rotatably supported by a vehicle.

As an example of such a power transmission device, the power transmission device disclosed in Patent Document 1 is arranged at the shaft center of the planetary gear mechanism and a cylindrical compound gear integrally including a ring gear of the planetary gear mechanism and an external gear. Rotation shaft, a carrier that rotatably supports a pinion gear that rotates integrally with the rotation shaft and that meshes with the ring gear, and a rolling bearing that rotatably supports a cylindrical compound gear. And the inner ring of the rolling bearing is externally fitted to a tubular support member formed in the housing.

JP, 2005-52373, A JP, 2015-215061, A

However, if the outer ring is a loose fit with respect to the support member, for example, in a situation where a large load is not applied to the bearing such as during EV running when the engine is stopped, the inner ring slides while In a situation where a heavy load is applied to the bearing after shifting to HV running, the inner ring may be pressed against the support member and wear due to creep may occur between the inner ring and the support member. In order to prevent the occurrence of such wear, it is conceivable to dispose an annular elastic body between the inner ring and the support member as described in Patent Document 2, for example. However, in that case, the number of parts may increase.

Therefore, the present invention has been made in view of the above circumstances, and it is an object of the present invention to suppress the occurrence of wear between the inner ring and the support member without increasing the number of parts. It is to provide a support structure for a power transmission device.

In order to achieve such an object, a support structure for a power transmission device for a vehicle according to an aspect of the present invention is
A tubular gear member having a gear on the outer peripheral side is rotatably supported by a support member by a bearing having an outer ring internally fitted to the inner peripheral surface of the gear member and an inner ring externally fitted to the outer peripheral surface of the support member. A power transmission device configured to support,
In the outer fitting support portion of the support member that fits and supports the inner ring, a lubricating groove into which lubricating oil flows is provided in at least one of the support member and the inner ring,
A bearing member supported by the support member and constituting a bearing different from the bearing is extended toward the end of the lubricating groove on the downstream side in the lubricating oil flow direction,
In the outer fitting support portion, an oil sump is formed between the support member and the inner ring.

According to such a support structure for a power transmission device according to an aspect of the present invention, the lubricating oil is held by an oil reservoir formed between the support member and the inner ring, so that the lubricant between the support member and the inner ring is retained. Occurrence of wear is suppressed. Further, since the oil sump is formed between the support member and the inner ring by using the bearing member that constitutes another bearing, the number of parts does not increase.

1 is a skeleton diagram showing a main part of a hybrid vehicle including a power transmission device to which the present invention is applied. It is sectional drawing which shows embodiment which applied this invention to the power transmission device shown by the skeleton figure of FIG. It is sectional drawing which follows the III-III line of FIG.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

FIG. 1 is a skeleton diagram showing a main part of a hybrid vehicle including a power transmission device to which the present invention is applied. The hybrid drive device is a so-called two-motor type drive device, and includes an engine (ENG) 1 and two rotary electric machines 2 and 3 as drive force sources. The engine 1 is an internal combustion engine such as a gasoline engine or a diesel engine, and the first rotating electric machine 2 is preferably a motor generator (hereinafter also referred to as MG1) capable of regenerating energy and outputting power. Similarly, the second rotary electric machine 3 is preferably a motor generator (hereinafter, also referred to as MG2). A power split mechanism that splits the power output from the engine 1 into a first rotary electric machine (MG1) 2 and an output member is provided. The power split mechanism can be configured by a differential mechanism such as a planetary gear mechanism, and in the example shown in FIG. 1, is configured by a single pinion type planetary gear mechanism 4.

In the planetary gear mechanism 4, a plurality of (for example, three) pinion gears 7 meshing with the sun gear 5 and the ring gear 6 are arranged between the sun gear 5 and the ring gear 6, and these pinion gears 7 are rotated by a carrier 8. And it is held so that it can revolve. The structure of holding the pinion gear 7 by the carrier 8 is the same as the structure of a conventionally known planetary gear mechanism, as will be described later.

The carrier 8 is a so-called input element, and is configured to transmit the power from the engine 1. That is, the crankshaft of the engine 1 on the axis C1 and the input shaft 9 connected to the carrier 8 are connected via a damper mechanism (not shown).

Further, on the same axis (axis C1), the first rotating electric machine (MG1) 2 is arranged on the side opposite to the engine 1 with the planetary gear mechanism 4 interposed therebetween. The rotor of the first rotary electric machine 2 is connected to the sun gear 5 via the rotor shaft 2a. Therefore, the sun gear 5 is a so-called reaction force element. The rotor shaft 2a of MG1 and the sun gear shaft to which the rotor shaft 2a is connected are hollow shafts, and the pump shaft 12 is inserted inside the hollow shafts. One end of the pump shaft 12 is connected to the engine 1 via the input shaft 9, and an oil pump (mechanical oil pump; MOP) 13 is connected to the other end. The MOP 13 is driven by the engine 1 to generate a hydraulic pressure for control and a hydraulic pressure for lubrication. Further, a second oil pump (electric oil pump; EOP) (not shown) driven by an electric motor to secure the hydraulic pressure when the engine 1 is stopped is provided in parallel with the MOP 13 separately. ing.

Further, the ring gear 6 in the planetary gear mechanism 4 constituting the power split mechanism serves as a so-called output element, and together with the ring gear 6 which is the internal gear, the output gear which is the external gear corresponding to the output member. 15 are provided. The output gear 15 is connected via a counter gear unit 16 to a differential gear device (Diff) 17 that rotates around an axis C4. That is, the driven gear 19 attached to the counter shaft 18 on the axis C2 meshes with the output gear 15. A drive gear 20 having a smaller diameter than the driven gear 19 is formed or attached to the counter shaft 18, and the drive gear 20 meshes with a ring gear 21 in the differential gear device 17. Driving force is output from the differential gear device 17 to the left and right drive wheels 22. The driven gear 19 is meshed with another drive gear 23 provided on the rotor shaft 3a on the axis C3 of the second rotary electric machine (MG2) 3. That is, the torque of the second rotary electric machine 3 is added to the torque output from the output gear 15.

The first rotating electric machine 2 and the second rotating electric machine 3 are electrically connected to each other via a power storage device or an inverter (not shown), and the electric power generated by the first rotating electric machine 2 is supplied to the second rotating electric machine 3. It is configured to be able to.

The hybrid vehicle described above can selectively set three traveling modes of a hybrid mode (HV mode), a two-motor mode, and a one-motor mode. In the HV mode, the power output from the engine 1 is split by the power split mechanism into the first rotary electric machine 2 side and the output gear 15 side, and the electric power generated by the first rotary electric machine 2 functioning as a generator is rotated to the second rotary electric machine. This is a traveling mode in which the output torque of the second rotary electric machine 3 is supplied to the electric machine 3 and the torque of the output gear 15 is added to the torque of the output gear 15 in the counter gear unit 16. In the two-motor mode, the engine 1 is stopped, the first rotary electric machine 2 and the second rotary electric machine 3 are operated as a driving force source for EV running, and EV running is performed by the power of these two rotary electric machines 2 and 3. Mode. In that case, the carrier 8 is fixed by a brake mechanism (not shown). Therefore, the power split mechanism functions as a reduction mechanism between the first rotary electric machine 2 and the output gear 15. The one-motor mode is a mode in which EV traveling is performed using the second rotary electric machine 3 as a driving force source.

Here, an embodiment in which the present invention is applied to the power transmission device shown in the skeleton diagram of FIG. 1 will be described with reference to FIG. FIG. 2 is a cross-sectional view showing a configuration of a housing or a case that supports a bearing that rotatably supports a shaft that holds a gear, as reference numeral 100 in the skeleton diagram of FIG. FIG. 2 shows a part of a portion corresponding to the axis C1 in the power transmission device described above.

In the embodiment shown in FIG. 2, the input shaft 9, the planetary gear mechanism 4 constituting the power split mechanism, and the ring gear 6 and the output gear 15 which rotate about the axis C1 and the inner circumference of the cylindrical member are arranged. A composite gear 25 is shown integrally formed on the side and the outer peripheral side, respectively, and the cylindrical composite gear 25 is supported by the housing 100 via the first and second bearings 102 and 104. The planetary gear mechanism 4 includes a sun gear 5, a ring gear 6, and a carrier 8 integrally fixed to a collar portion 9 a formed on the input shaft 9 by press fitting, welding, or the like. The sun gear 5 and the ring gear 6 Is engaged with a pinion gear 7 rotatably arranged on a carrier 8. The input shaft 9 corresponds to a rotary shaft, is rotatably supported by the housing 100 through a plurality of bearings around the axis C1, and is driven by the power of the engine 1 to rotate around the axis C1. To be done. The axis C1 of the input shaft 9 corresponds to the axis of the planetary gear mechanism 4, and the sun gear 5 and the ring gear 6 are rotatably arranged around the axis C1.

A plurality of (for example, three) pinion pins 8a are integrally fixed to the carrier 8 in parallel with the axis C1 by press fitting, welding, or the like, and the pinion gear 7 is provided through the pair of needle bearings 8b. 8a is rotatably arranged. The carrier 8 is provided with a through hole, and the pinion pin 8a is integrally fixed to the carrier 8 in a state where the pinion pin 8a penetrates the through hole and the end face in the axial direction is substantially flush with the side face of the carrier 8. Has been done. The carrier 8 is provided on both sides in the axial direction with the pinion gear 7 interposed therebetween, and both ends of the pinion pin 8 a are fixed to the carrier 8. The carriers 8 on both sides are integrally formed with each other, and the carrier 8 on the right side of the drawing is integrally fixed to the input shaft 9. The input shaft 9 is provided with a collar portion 9a formed integrally therewith, and the carrier 8 is fitted and fixed integrally to the outer peripheral side of the collar portion 9a. A thrust bearing 106 is arranged between the collar portion 9a and the housing 100, and the axial positions of the input shaft 9 and the carrier 8 are defined in a state of being rotatable around the axis C1.

The sun gear 5 is rotatably arranged on the outer peripheral side of the input shaft 9 via a needle bearing 5a, and also the rotor shaft 2a of the first rotary electric machine (MG1) 2 shown in FIG. 1 via a spline 5b. Is connected so that it cannot rotate relative to. A thrust bearing 108 is provided between the sun gear 5 and the collar portion 9a, and a thrust bearing 110 is provided between the sun gear 5 and the housing 100. The sun gear 5 rotates about the axis C1. Axial position is defined where possible.

As described above, the ring gear 6 is integrally provided with the output gear 15 which is an external gear, and the ring gear 6 and the output gear 15 constitute a cylindrical composite gear 25. The output gear 15 is meshed with a counter gear 19 provided on a counter shaft 18 arranged in parallel with the input shaft 9, and further from the counter shaft 18, a drive gear 20, a ring gear 21 in the differential gear device 17, and the like. Power is transmitted to the drive wheel 22 side via the. The composite gear 25 projects outward in the axial direction from the carrier 8, and is rotatable around the axis C1 by the housing 100 outside the carrier 8 via the first and second rolling bearings 102 and 104. It is supported. These first and second rolling bearings 102, 104 are arranged on the inner peripheral side of the axial end portion of the compound gear 25 having a cylindrical shape.

Further, a supply oil passage 30 is provided at the axis C1 of the input shaft 9 in the present embodiment, and lubricating oil is supplied from the oil pump 13 shown in FIG. Then, the thrust bearing 106 is lubricated by the lubricating oil discharged from the first radial oil passage 30 a communicating with the supply oil passage 30, and the lubricating oil flowing through the thrust bearing 106 to the outer peripheral side is further By being blown to the outer peripheral side by the centrifugal force, it is received by the oil receiver 32 attached to the side surface of the carrier 8 and having the through hole 32a, and the pinion gear 7 and the second rolling bearing 104 are lubricated. Further, the needle bearing 5a is lubricated and the thrust bearing 108 is lubricated by the lubricating oil discharged from the second radial oil passage 30b communicating with the supply oil passage 30.

Further, in the embodiment shown in FIGS. 2 and 3, in the first rolling bearing 102 described above, the outer ring 102a of the first rolling bearing 102 is tightly fitted to the inner peripheral surface of the compound gear 25 having a cylindrical shape, and the inner ring 102b of the first rolling bearing 102 is the housing. A clearance is fitted to the outer peripheral surface of a cylindrical support member 100 a formed to project from 100. The outer fitting support portion of the support member 100a that supports the inner ring 102b is provided with a lubricating groove 100b that extends in the axial direction parallel to the axis C1.

On the other hand, the thrust bearing 110 provided between the tip of the cylindrical support member 100a formed so as to project from the housing 100 and the sun gear 5 described above has a rolling roller 110b held in the cage 110a. It is formed so as to be rollable between the left bearing race 110c and the right bearing race 110d. In the present embodiment, the left bearing race 110c has an L-shaped cross section of the inner ring portion 110ci extending in the axial direction parallel to the axis C1 and the radial ring portion 110cp extending in the radial direction orthogonal to the axis C1. It is formed with a shape. The right bearing race 110d includes an inner ring portion 110di and an outer ring portion 110do that extend in the axial direction parallel to the axis C1 and a radial ring portion that extends between them in a radial direction orthogonal to the axis C1. It is formed with 110 dp.

Here, the left bearing race 110c, which is formed with an L-shaped cross-sectional shape, has its inner ring portion 110ci press-fitted and held in the opening of the distal end portion of the cylindrical support member 100a. On the other hand, the radial ring portion 110cp extends toward the downstream end of the lubricating groove 100b in the lubricating oil flow direction (indicated by arrow Y). Thus, the inner end of the outlet of the lubrication groove 100b is closed by the outer end of the radial ring portion 110cp, in other words, the area of the outlet of the lubrication groove 100b is reduced to reduce the area of the support member 100a and the first rolling bearing 102. An oil sump 120 is formed between the inner ring 102b and the inner ring 102b.

In the present embodiment configured as described above, a part of the lubricating oil that flows out from the radial oil passages 30a and 30b of the input shaft 9 and is scattered to the outer peripheral side by the centrifugal force is the left end of the composite gear 25. It is guided between the portion and the housing 100 and flows in the direction of the arrow X, and reaches the oil sump 120 formed between the support member 100a and the inner ring 102b of the first rolling bearing 102. Therefore, even if the inner ring 102b rotates with respect to the support member 100a due to the creep of the first rolling bearing 102, the presence of the lubricating oil retained in the oil sump 120 causes a difference between the inner ring 102b and the support member 100a. Wear is suppressed.

Further, in the present embodiment, the oil sump 120 is formed by using the left bearing race 110c that is a bearing member that constitutes the existing thrust bearing 110 that is a bearing different from the first rolling bearing 102. Therefore, the number of parts does not increase.

Further, another embodiment of the present invention will be described. In the above-described embodiment, the oil groove 120 is formed by forming the lubricating groove 100b in the support member 100a. However, instead of or in addition to this, the lubricating groove in the axial direction is formed on the inner peripheral surface of the inner ring 102b. May be formed. However, in this case, in order to reduce the outlet area of the lubrication groove, it is necessary to adjust the diameter of the outer end portion of the radial annular portion 110cp of the left bearing race 110c, which is a bearing member of another bearing. is there.

The embodiments of the present invention have been described above in detail with reference to the drawings. However, these are merely embodiments, and the present invention is implemented in various modified and improved modes based on the knowledge of those skilled in the art. be able to.

4 Planetary gear mechanism 5 Sun gear 6 Ring gear 8 Carrier 9 Input shaft 15 External gear (output gear)
25 compound gear 100 housing 100a support member 100b lubrication groove 102 first rolling bearing 102a outer ring 102b inner ring 110 thrust bearing 110c left bearing race 120 oil sump

Claims (1)

A tubular gear member having a gear on the outer peripheral side is rotatably supported by a support member by a bearing having an outer ring internally fitted to the inner peripheral surface of the gear member and an inner ring externally fitted to the outer peripheral surface of the support member. A power transmission device configured to support,
In the outer fitting support portion of the support member that fits and supports the inner ring, a lubricating groove into which lubricating oil flows is provided in at least one of the support member and the inner ring,
A bearing member supported by the support member and constituting a bearing different from the bearing is extended toward the end of the lubricating groove on the downstream side in the lubricating oil flow direction,
A support structure for a power transmission device, wherein an oil sump is formed between the support member and the inner ring in the outer fitting support portion.

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