JP6795434B2 - Lubrication structure of power transmission device - Google Patents

Description

The present invention relates to a lubrication structure of a power transmission device using a planetary gear mechanism.

In a power transmission device using a planetary gear mechanism, the structure for supplying lubricating oil to the bearing portion of the pinion gear is an oil passage provided along the axial direction of the rotating shaft arranged at the center of rotation of the planetary gear mechanism. The supplied lubricating oil is discharged through an oil hole opened along the radial direction of the same rotation axis, and the released lubricating oil is extended along the radial direction inside the carrier. A structure is known in which a path and an oil path formed along the axial direction and the radial direction of the support shaft of the pinion gear are passed through the bearing portion.

Japanese Unexamined Patent Publication No. 02-154837

However, if an oil passage along the axial direction cannot be formed on the rotating shaft arranged at the center of rotation of the planetary gear mechanism, the configuration of the prior art does not hold, and another configuration needs to be considered.

An example in which an oil passage along the axial direction cannot be formed on the rotation shaft arranged at the center of rotation is a case where a planetary gear mechanism is used as a final reduction gear of a power transmission device for a vehicle. In this case, the rotating shaft arranged at the center of rotation of the planetary gear mechanism is generally a drive shaft connected to the wheels, and an oil passage for supplying lubricating oil for the planetary gear mechanism is provided to the drive shaft. It is extremely difficult to form.
Therefore, a configuration is conceivable in which the lubricating oil is supplied from the outer side of the planetary gear mechanism to the space portion on the inner diameter side of the carrier, but the lubricating oil is formed on the carrier simply by supplying the lubricating oil so as to accumulate in the space portion. It is considered that sufficient lubricating oil cannot be supplied to the bearing portion of the pinion gear because it is not accurately guided to the lubricating oil passage and is discharged from a gap or the like existing nearby.

The present invention has been devised in view of such a problem, and an object of the present invention is to appropriately secure lubrication to a bearing portion of a pinion gear in a power transmission device using a planetary gear mechanism, and in particular, a rotation center of the planetary gear mechanism. The effect is exhibited in a structure in which it is difficult to form an oil passage on the rotating shaft arranged in the above.

(1) In order to achieve the above object, the lubrication structure of the power transmission device of the present invention includes a planetary gear mechanism including a sun gear, a pinion gear, a ring gear and a carrier for supporting the pinion gear, and a rotation center of the planetary gear mechanism. A radial direction of the carrier arranged on one side along the line, including a rotating member fitted to the sun gear so as to rotate integrally with the sun gear, and arranged on the rotating member side of the planetary gear mechanism. It is a lubrication structure of a power transmission device that supplies lubricating oil to the bearing portion of the pinion gear via a first oil passage extending along the route, and the rotating member is fitted to a fitting portion between the sun gear and the rotating member. A second oil passage is formed so as to communicate between both side surfaces of the sun gear to allow the lubricating oil to flow, and the tooth surface of the sun gear is extended along the rotation center line to a position facing the opening of the first oil passage. A guide groove for guiding lubricating oil to the opening is formed on the tooth surface of the sun gear facing the opening.

(2) It is preferable that the guide groove is formed on the tooth surface on the side facing the same rotation direction in the rotation direction when the power transmission mechanism is normally used.
(3) It is preferable to mount the annular member on the sun gear so that the outer diameter surface is adjacent to and faces the inner diameter surface of the carrier located between the opening and the end surface of the pinion gear.

(4) Further, the lubrication structure of the power transmission device of the present invention is arranged on one side of the planetary gear mechanism having a sun gear, a pinion gear, a ring gear and a carrier supporting the pinion gear, and the planetary gear mechanism along the rotation center line. A second carrier, which is provided with a rotating member fitted to the sun gear so as to rotate integrally with the sun gear, and which is arranged on the rotating member side of the planetary gear mechanism along the radial direction of the carrier. It is a lubrication structure of a power transmission device that supplies lubricating oil to the bearing portion of the pinion gear via one oil passage, and communicates between both side surfaces of the rotating member through a fitting portion between the sun gear and the rotating member. A second oil passage for passing lubricating oil is formed, and the tooth surface of the sun gear is extended along the rotation center line to a position facing the opening of the first oil passage, and the outer diameter surface is the said. An annular member is mounted on the sun gear so as to be adjacent to and face the inner diameter surface of the carrier located between the opening and the end face of the pinion gear.
Characterized by

(5) Further, it is preferable that the side surface of the annular member on the opening side is located on the pinion gear side from the center of the opening.

According to the present invention, the lubricating oil supplied to the space on the inner diameter side of the carrier via the second oil passage is along the guide groove formed on the tooth surface of the sun gear by the centrifugal force generated by the rotation of the sun gear. Since it is guided to the opening of the first oil passage, a large amount of lubricating oil can be supplied to the bearing portion of the pinion gear via the first oil passage.

Further, according to the present invention, by mounting the annular member on the sun gear so that the outer diameter surface is adjacent to and faces the carrier inner diameter surface located between the opening and the pinion gear end surface, the carrier inner diameter side It is possible to suppress the lubricating oil supplied to the space portion from flowing out toward the meshing portion (central portion of the planetary gear mechanism) between the sun gear and the pinion gear, and it is possible to supply more lubricating oil to the bearing portion. ..

It is a partial vertical sectional view which shows the structure of the power transmission apparatus to which the lubrication structure which concerns on one Embodiment of this invention is applied. FIG. 5 is an enlarged view showing an enlarged range indicated by reference numeral A in FIG. It is a perspective view which partially shows the extension part of the sun gear tooth surface in one Embodiment of this invention.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
It should be noted that the embodiments shown below are merely examples, and there is no intention of excluding the application of various modifications and techniques not specified in the following embodiments. Each configuration of the following embodiments can be variously modified and implemented without departing from the purpose thereof, and can be selected as necessary or combined as appropriate.

A gear (rotating member) 12 that meshes with the output gear of the transmission is supported via two bearings 14 in a case 10 of a transmission (not shown) mounted on the vehicle. The gear 12 is fitted to the outer peripheral surface of the tubular extension portion 20 extending axially from the main body of the sun gear 18 of the planetary gear mechanism 16 as the final reduction gear via a spline 21 so as not to rotate relative to each other. ..

The planetary gear mechanism 16 has a conventionally known structure, and includes a sun gear 18, a plurality of pinion gears 22 that mesh with the sun gear 18 (only one is described in the drawing), and a ring gear that meshes with the pinion gear 22 on the outer circumference of the pinion gear 22. It is composed of 24 and carriers 28 and 29 that rotatably support the pinion gear 22 via the support shaft 26.
The carriers 28 and 29 are connected and fixed to the case 10 at positions (not shown).

The ring gear 24 has a tubular extension portion 30 extending in the axial direction from the main body thereof, and is connected to the differential case 36 of the differential mechanism 34 by a bolt 32.

The differential mechanism 34 has a conventionally well-known structure, includes two pinion gears 38 and two side gears 40 (both of which are only partially described in the figure), and the two side gears 40 are connected to the left and right drive shafts 42, respectively. ing.
A cylindrical extension 44 into which the drive shaft 42 is inserted is spline-connected at the inner end (left end in the drawing) of the differential case 36, and the outer end (FIG.) of the cylindrical extension 44 is splined. The middle and right end portions) are supported by the case 10 via a bearing 46.
An oil seal 48 that tightly holds between the outer peripheral surface of the drive shaft 42 and the case 10 is mounted on the outer side of the bearing 46.

Here, the lubrication structure according to the embodiment of the present invention will be described.
In the case 10, an oil supply path 52 for supplying lubricating oil into a space 50 formed near the outer end (right end in the drawing) of the spline 21 fitting portion between the gear 12 and the tubular extension portion 20 is formed. Lubricating oil is supplied to the oil supply passage 52 from an oil pump or the like via an oil passage (not shown) communicated from the outside of the case 10.

In the spline 21, one of the spline teeth formed on either the gear 12 side or the tubular extension portion 20 side is missing over the entire length thereof, whereby the space portion 50 and the carrier 28 are missing. An oil passage (second oil passage) 56 that communicates with the space portion 54 formed on the inner diameter side of the gear 12 (that is, communicates between both side surfaces of the gear 12) is formed.

On the other hand, an oil passage (first oil passage) 58 is formed inside the carrier 28 arranged on the gear 12 side along the radial direction, and the support shaft 26 of the pinion gear 22 has the oil passage 58. The first radial oil passage 60 drilled at the same position along the radial direction, the axial oil passage 62 provided along the axial direction of the support shaft 26 and communicating with the oil passage 60, and the radial direction of the support shaft 26. A second radial oil passage 66 is formed so as to communicate with the axial oil passage 62 and the bearing portion 64 for bearing the pinion gear 22.

Further, as shown in FIG. 2, the sun gear 18 is provided with an extension tooth surface portion 68 whose tooth surface is extended to a position facing the opening 59 of the oil passage 58, and a snap ring 74 (annular member) is attached to the sun gear 18. The snap ring 74 is mounted at a position where its outer diameter surface 70 is adjacent to and faces the inner diameter surface 72 of the carrier 28 located between the opening 59 and the carrier 28 side end surface of the pinion gear 22.
In the above configuration, the plate thickness of the snap ring 74 is adjusted so that the side surface 76 on the opening 59 side of the snap ring 74 is located closer to the pinion gear 22 than the center 78 of the opening 59.

Further, a guide groove 80 for guiding the lubricating oil to the opening 59 is formed on the tooth surface of the extended tooth surface portion 68 along the radial direction.

Assuming that the arrow B shown in FIG. 3 is the rotation direction of the sun gear 18 when the vehicle is traveling forward (the rotation direction when the power transmission mechanism is normally used), the guide groove 80 is a tooth surface toward the rotation direction B, in other words, For example, it is formed on the tooth surface that presses against the tooth surface of the pinion gear 22 during forward traveling and is responsible for power transmission.

With the above configuration, the lubricating oil supplied from the oil supply passage 52 to the space portion 50 flows into the space portion 54 formed on the inner diameter side of the carrier 28 via the oil passage 56.
The lubricating oil in the space portion 54 is guided toward the opening 59 of the oil passage 58 along the guide groove 68 by the centrifugal force accompanying the rotation of the sun gear 18, that is, the rotation of the extension tooth surface portion 68, and the oil passage from this opening 59. It flows into 58.
Then, the lubricating oil that has flowed into the oil passage 58 flows through the first radial oil passage 60, the axial oil passage 62, and the second radial oil passage 66, and is supplied to the bearing portion 64 to provide the bearing 64. Lubricate and cool.

Since the lubricating structure of the power transmission device according to the embodiment of the present invention is configured as described above, the lubricating oil supplied to the space 54 on the inner diameter side of the carrier 22 via the oil passage 56 is the sun gear 18. The centrifugal force generated by the rotation guides the sun gear 18 to the opening 59 of the oil passage 58 along the guide groove 80 formed on the tooth surface of the sun gear 18, so that a large amount of lubricating oil is supplied to the bearing of the pinion gear 22 via the oil passage 58. It becomes possible to supply to the unit 64.

Further, according to one embodiment of the present invention, the snap ring so that the outer diameter surface 70 faces the inner diameter surface 72 of the carrier 28 located between the opening 59 and the end surface of the pinion gear 22 on the carrier 28 side. By mounting the 74 on the sun gear 18, the lubricating oil supplied to the space 54 on the inner diameter side of the carrier 28 is suppressed from flowing out toward the meshing portion (central portion of the planetary gear mechanism) between the sun gear 18 and the pinion gear 22. It is possible to supply more lubricating oil to the bearing portion 64.

Further, since the guide groove 80 is formed on the tooth surface in the direction of rotation of the sun gear 18 (rotation direction when the power transmission mechanism is normally used) when the vehicle is traveling forward, the forward traveling occupies most of the vehicle traveling. Occasionally, it becomes possible to supply more lubricating oil to the bearing portion 64.

Although the embodiments of the present invention have been described above, the present invention can be implemented by appropriately modifying such embodiments.
For example, in the above embodiment, the snap ring 74 is used to suppress the outflow of the space portion 54, but the inner diameter surface 72 of the carrier 28 located between the opening 59 and the end surface of the pinion gear 22 on the carrier 28 side is the sun gear 18. The snap ring 74 can be omitted if it is formed so as to be as close as possible to the outer peripheral surface of the above.

Further, the guide groove is formed on the tooth surface in the direction in which the sun gear 18 rotates when the vehicle is traveling backward (that is, one tooth of the sun gear 18 is opposite to the surface on which the guide groove 80 is formed in the above embodiment. It may be formed on a surface).

Further, in the present embodiment, an example in which the lubrication structure of the power transmission device of the present invention is applied to the final deceleration mechanism in the power transmission device for a vehicle is shown, but the lubrication structure of the power transmission device of the present invention is not limited to this. , A power transmission device in which a planetary gear mechanism and a rotating member are arranged adjacent to each other can be widely applied.

12 gears (rotating members)
16 Planetary gear mechanism 18 Sun gear 21 Spline fitting 22 Pinion gear 24 Ring gear 28,29 Carrier
56 Oil channel (second oil channel)
58 Oil channel (first oil channel)
59 Aperture 64 Bearing part 68 Extension tooth surface part 70 Outer diameter surface 72 Inner diameter surface 74 Snap ring (annular member)
80 guide groove

Claims (5)

A planetary gear mechanism having a sun gear, a pinion gear, a ring gear, and a carrier that supports the pinion gear,
It is provided with a rotating member arranged on one side along the rotation center line of the planetary gear mechanism and fitted to the sun gear so as to rotate integrally with the sun gear.
Lubricating structure of a power transmission device that supplies lubricating oil to the bearing portion of the pinion gear via a first oil passage extending along the radial direction of the carrier arranged on the rotating member side of the planetary gear mechanism. And
A second oil passage is formed in the fitting portion between the sun gear and the rotating member so as to communicate between both side surfaces of the rotating member and allow the lubricating oil to flow.
The tooth surface of the sun gear is extended along the rotation center line to a position facing the opening of the first oil passage.
A lubrication structure for a power transmission device, characterized in that a guide groove for guiding lubricating oil to the opening is formed on the tooth surface of the sun gear facing the opening. The power transmission device according to claim 1, wherein the guide groove is formed on a tooth surface on the side facing the rotation direction in the rotation direction when the power transmission mechanism is normally used. Lubricating structure. The first or second aspect of the present invention, wherein the annular member is mounted on the sun gear so that the outer diameter surface is adjacent to and faces the inner diameter surface of the carrier located between the opening and the end surface of the pinion gear. Lubrication structure of the power transmission device. A planetary gear mechanism having a sun gear, a pinion gear, a ring gear, and a carrier that supports the pinion gear,
It is provided with a rotating member arranged on one side along the rotation center line of the planetary gear mechanism and fitted to the sun gear so as to rotate integrally with the sun gear.
Lubricating structure of a power transmission device that supplies lubricating oil to the bearing portion of the pinion gear via a first oil passage extending along the radial direction of the carrier arranged on the rotating member side of the planetary gear mechanism. And
A second oil passage is formed in the fitting portion between the sun gear and the rotating member to communicate between both side surfaces of the rotating member and allow the lubricating oil to flow.
The tooth surface of the sun gear is extended along the rotation center line to a position facing the opening of the first oil passage.
A lubrication structure for a power transmission device, characterized in that an annular member is mounted on the sun gear so that the outer diameter surface is adjacent to and faces the carrier inner diameter surface located between the opening and the pinion gear end surface. The lubrication structure for a power transmission device according to claim 4, wherein the side surface of the annular member on the opening side is configured to be located on the pinion gear side from the center of the opening.

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