JPH11210867A - Pinion shaft end lubricating structure for planetary gear - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the durability of thrust washers externally inserted into the end part of a pinion shaft. SOLUTION: An about V-shaped oil discharge grooves 17 spreading out from the inner peripheral edge of a through hole 4b toward the outer peripheral edge of a carrier plate 3 is formed on the bearing surface of the carrier plate 3 facing the axially outside thrust washer 14 out of two thrust washers 14 externally inserted in the end part of a pinion shaft 6. A pin 10 is arranged at the center part of the V-shape of the oil discharge grooves 17 formed on the bearing surface of the carrier plate 3, and thus the oil discharge grooves 17 are adapted to be not overlapped with the pin 10 in the direction of thickness of the carrier plate 3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an end lubrication structure for a pinion shaft of a planetary gear.

[0002]

2. Description of the Related Art As a conventional end lubrication structure for a pinion shaft of this kind, there is known a structure disclosed in Japanese Utility Model Laid-Open Publication No. 64-20558.

In this structure, as shown in FIG. 7, a pinion shaft c having both ends fixed to carrier plates b, b of a carrier a opposed to each other is provided. A pinion d is provided at the center of the pinion shaft c with a needle. It is rotatably supported via a bearing e. Pinion shaft c
Washers f are located between the pinion d and the carrier plates b.

[0004] An oil hole g is opened on the outer peripheral surface of the pinion shaft c facing the needle bearing e. The oil supplied to the needle bearing e from the oil hole g reduces the thrust force of the needle bearing e and the pinion d. The lubrication with the receiving washer f is performed.

However, in such a pinion shaft end lubrication structure, when a thrust force is generated in the pinion d, the carrier plate b and the washer f receiving the thrust force of the pinion d come into close contact with each other, and the oil is discharged to the outside. As a result, there is an inconvenience that sliding heat easily occurs on the contact surface between the carrier plate b and the washer f.

Therefore, in order to eliminate such inconvenience,
JP-A-3-14947 discloses an end lubrication structure for a pinion shaft. In this structure, as shown in FIG. 8, an oil discharge groove h extending from the inner peripheral portion to the outer peripheral portion is formed on the face of the washer f, and the oil supplied to the needle bearing e is supplied along the groove h. By discharging the oil to the outside, a sufficient amount of oil is supplied to the surface of the washer f, thereby solving the above-described disadvantage.

As another lubrication structure for the end of the pinion shaft, as shown in FIG. 9, a seating surface of the carrier plate b facing the washer f is provided on the inner peripheral side of the carrier plate b from the end of the pinion shaft c. An oil inflow groove g extending toward is formed.

The oil inflow groove g is formed so that the center line thereof coincides with the radial center lines S of the carrier plate b and the pinion shaft c, and the oil inflow groove g of the carrier plate b extends along the oil inflow groove g. By lubricating the end of the pinion shaft c by allowing oil to flow into the end of the pinion shaft c from the inner peripheral side.

[0009]

However, in the former lubricating structure of the end of the pinion shaft shown in FIG. 8, since the oil discharge groove h is formed on the washer f surface, the strength of the washer f is reduced. Inferior in durability.

On the other hand, in the latter pinion shaft end lubrication structure shown in FIG. 9, the oil inflow groove g is formed along each radial center line S of the carrier plate b and the pinion shaft c. The oil inflow efficiency due to the rotation of the carrier plate b is low, and as a result, sliding heat easily occurs in the pinion shaft c, the washer f, the needle bearing e, and the carrier plate b due to a temperature rise due to insufficient lubrication.

Further, in order to prevent rotation and detachment of the pinion shaft c, a pin h press-fit from the outer peripheral side of the carrier plate b in the radial direction of the carrier plate b is made to penetrate in the radial direction of the pinion shaft c so that the pinion shaft c When the end is fixed to the carrier plate b,
If the thickness of the carrier plate b is small, there is a disadvantage that when the pin h is driven in, the tip of the pin h protrudes into the oil inflow groove, and the pressure input is reduced.

SUMMARY OF THE INVENTION The present invention has been made to solve such a disadvantage, and the invention of claim 1 is to improve the durability of a washer externally inserted into an end of a pinion shaft. An object of the present invention is to provide a shaft end lubrication structure.

Another object of the present invention is to provide an end lubrication structure for a pinion shaft of a planetary gear, which can improve the efficiency of oil inflow into an oil inflow groove by rotation of a carrier plate.

[0014]

In order to achieve the above object, an end lubricating structure for a pinion shaft of a planetary gear according to the present invention comprises a pinion shaft having an end fixed to a carrier plate, and the pinion shaft. A pinion rotatably supported via a bearing, and a washer externally inserted into the pinion shaft between the pinion and the carrier plate, and an oil opening at a position facing the bearing of the pinion shaft. In a planetary gear configured to supply oil to the bearing through a hole, an oil discharge groove extending from an end of the pinion shaft toward an outer peripheral side of the carrier plate is provided on a seat surface of the carrier plate facing the washer. It is characterized by having been formed.

According to a second aspect of the present invention, in the end lubrication structure of the pinion shaft of the planetary gear, the oil discharge groove is formed in a substantially V-shape extending from the end of the pinion shaft toward the outer peripheral side of the carrier plate. It is characterized by the following.

According to a third aspect of the present invention, there is provided an end lubrication structure for a pinion shaft of a planetary gear, wherein a pin press-fitted in a radial direction of the carrier plate from an outer peripheral side of the carrier plate penetrates in a radial direction of the pinion shaft. An end of the pinion shaft is fixed to the carrier plate, and the oil discharge groove is formed at a position where the oil discharge groove does not overlap the pin in a thickness direction of the carrier plate.

According to a fourth aspect of the present invention, there is provided a planetary gear pinion shaft end lubricating structure, comprising: a pinion shaft having an end fixed to a carrier plate; and a pinion rotatably supported by the pinion shaft via a bearing. A planetary gear including a washer externally inserted into the pinion shaft between the pinion and the carrier plate, wherein the oil flows into an end of the pinion shaft from an inner peripheral side of the carrier plate. A substantially V-shaped oil inflow groove extending from an end of the pinion shaft toward an inner peripheral side of the carrier plate is formed on a seat surface of the carrier plate facing the washer.

According to a fifth aspect of the present invention, in the planetary gear pinion shaft end lubrication structure, the carrier plate extends from the end of the pinion shaft toward the outer peripheral side of the carrier plate on the bearing surface facing the washer. A substantially V-shaped oil discharge groove is formed.

According to a sixth aspect of the present invention, in the planetary gear pinion shaft end lubrication structure, a pin press-fitted in a radial direction of the carrier plate from an outer peripheral side of the carrier plate is penetrated in a radial direction of the pinion shaft. An end of the pinion shaft is fixed to the carrier plate, and the oil inflow groove is formed at a position not overlapping the pin in a thickness direction of the carrier plate.

[0020]

According to the first aspect of the present invention, the oil discharged from the bearing is formed on the bearing surface of the carrier plate facing the washer by forming an oil discharge groove extending from the end of the pinion shaft toward the outer peripheral side of the carrier plate. Is discharged along the oil discharge groove, thereby making it possible to supply oil to the washer surface without reducing the strength of the washer.

According to a second aspect of the present invention, in addition to the first aspect, the oil discharge groove is formed in a substantially V-shape extending from the end of the pinion shaft toward the outer peripheral side of the carrier plate. To improve oil discharge efficiency by rotating

According to a third aspect of the present invention, in addition to the first or second aspect, a pin press-fitted in a radial direction of the carrier plate from an outer peripheral side of the carrier plate is made to penetrate in a radial direction of the pinion shaft so that the pinion shaft is rotated. When fixing the end of the shaft to the carrier plate, the oil discharge groove is formed at a position that does not overlap with the pin in the thickness direction of the carrier plate, so that when the pin is press-fitted, a thin plate formed by press working or the like, for example. A sufficient press-fit width can be obtained even if the carrier plate has a rectangular shape.

Further, by forming the oil discharge groove at a position where the oil discharge groove does not overlap the pin in the thickness direction of the carrier plate, the oil discharge groove can be prevented from rising when the oil discharge groove is pressed from the groove bottom side by press-fitting the pin. To reduce.

According to the fourth aspect of the present invention, a substantially V-shaped oil inflow groove extending from the end of the pinion shaft toward the inner peripheral side of the carrier plate is formed on the bearing surface of the carrier plate facing the washer. In addition, the oil inflow efficiency is improved by the rotation of the carrier plate.

According to a fifth aspect of the present invention, in addition to the fourth aspect of the present invention, a substantially V-shaped oil that extends from the end of the pinion shaft toward the outer peripheral side of the carrier plate on the bearing surface of the carrier plate facing the washer. By forming the discharge groove, the oil discharge efficiency is improved by the rotation of the carrier plate.

According to a sixth aspect of the present invention, in addition to the fourth or fifth aspect, a pin press-fitted in a radial direction of the carrier plate from an outer peripheral side of the carrier plate is made to penetrate in a radial direction of the pinion shaft. When the end of the shaft is fixed to the carrier plate, the oil inflow groove is formed at a position that does not overlap the pin in the thickness direction of the carrier plate, so that the tip of the pin jumps into the oil inflow groove when the pin is driven. Prevent from putting out.

[0027]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is an explanatory cross-sectional view for explaining an end lubrication structure of a pinion shaft of a planetary gear according to an embodiment of the present invention, and FIG.
FIG. 3 is a cross-sectional view as viewed from the direction of the arrow B in FIG. 2, and FIG. 4 is a cross-sectional view as viewed along the line CC in FIG. 1.

First, the structure of the planetary gear will be described. In FIG. 1, reference numeral 1 denotes a carrier, and the carrier 1 has carrier plates 2 and 3 which are arranged to face each other in the left-right direction. Through holes 4a, 4b are formed concentrically in the carrier plates 2, 3, respectively. On the inner peripheral surface of the through hole 4b on the carrier plate 3 side, pin holes 5a and 5b are formed 180 ° apart from each other in the circumferential direction.

The pin holes 5a extend radially outward of the carrier plate 3 and open to the outer periphery of the carrier plate 3, while the pin holes 5b extend radially inward of the carrier plate 3 and have a bottom. It is a hole. Both ends of the pinion shaft 6 are fitted into the through holes 4a and 4b, respectively.

The pinion shaft 6 has an oil passage 7 formed therein, and the oil flowing through the oil passage 7 flows out of an oil hole 8 opened on the outer peripheral surface of a substantially central portion of the pinion shaft 6 in the axial direction. Have been. Pin holes 9 corresponding to the above-described pin holes 5a and 5b are formed in the outer peripheral surface of the end portion of the pinion shaft 6 fitted into the through holes 4b on the carrier plate 3 side in a radial direction.

The axes of the pin hole 9 of the pinion shaft 6 and the pin holes 5a and 5b of the carrier plate 3 are made to coincide with each other, and in this state, the pin 10 is press-fitted through the pin hole 5a. The part is fixed to the carrier plate 3. In FIG. 1, reference numeral 11 denotes a seal ball driven into the oil passage 7 to seal the open end of the oil passage 7.

A pinion 12 is rotatably supported on the pinion shaft 6 via a needle bearing (bearing) 13. The pinion shaft 6 between the pinion 12 and the carrier plates 2, 3 receives the thrust force of the pinion 12. Thrust washers 14 are extrapolated two by two. A sun gear 15 and an internal gear 16 mesh with the pinion 12, and when the carrier 1 and the sun gear 15 or the internal gear 16 rotate relative to each other, the pinion 12 rotates.

At this time, oil is supplied to the needle bearing 13 from an oil hole 8 opened on the outer peripheral surface of the pinion shaft 6, and the supplied oil flows along the axial direction of the needle bearing 13 and is supplied to the end of the pinion shaft 6. Department,
Thereby, the needle bearing 13 and the thrust washer 14 are lubricated.

In this embodiment, the oil which has reached the end of the pinion shaft 6 is discharged to the outside as follows to supply sufficient oil to the thrust washer 14, and seizure occurs. Has been prevented.

That is, as shown in FIGS. 2 to 4, the carrier plates 2, 3 facing the axially outer thrust washer 14 among the two thrust washers 14 externally inserted at the end of the pinion shaft 6. Through holes 4 in the seat
A substantially V-shaped oil discharge groove 17 extending from the inner peripheral edges of the a and 4b to the outer peripheral edges of the carrier plates 2 and 3 is formed by pressing or cutting, whereby the thrust is transmitted along the outer periphery of the pinion shaft 6. The oil that has flowed out of the washer 14 is centrifugally generated by the rotation of the carrier 1 and the oil discharge groove 1
The guide plate 7 is guided to the outer peripheral side of the carrier plates 2 and 3 to be discharged to the outside.

As shown in FIGS. 2 and 3, a pin 10 is disposed at the center of the V-shape of an oil discharge groove 17 formed on the seating surface of the carrier plate 3. 17 does not overlap the pins 10 in the thickness direction of the carrier plate 3.

In the lubrication structure for the end portion of the pinion shaft of the planetary gear having the above structure, the oil discharge grooves 17 are provided on the bearing surfaces of the carrier plates 2 and 3 facing the thrust washer 14.
Is formed, so that the thrust washer 1
4 without lowering the strength of the thrust washer 14.
By supplying sufficient oil to the surface, the end of the pinion shaft 6 can be lubricated.

The oil discharge groove 17 is formed obliquely so as to gradually move away from the radial center lines S of the carrier plates 2 and 3 and the pinion shaft 6 toward the outer peripheral side of the carrier plates 2 and 3. In addition, it is possible to improve the discharge efficiency when discharging the oil using the centrifugal force due to the rotation of the carrier 1.

Further, the oil discharge groove 17 is provided on the carrier plate 3.
So that it does not overlap with the pin 10 in the thickness direction of
When press-fitting the pins 10 from the outer peripheral side of the carrier plate 3, a sufficient press-fit width can be obtained even if the carrier plate 3 is a thin plate formed by press working or the like.

Further, the oil discharge groove 17 is connected to the carrier plate 3.
By arranging the oil discharge groove 17 so as not to overlap with the pin 10 in the thickness direction of the oil discharge groove 17, it is possible to reduce the bulging deformation of the oil discharge groove 17 when the oil discharge groove 17 is pressed from the groove bottom side when the pin 10 is pressed. Thus, the oil discharge groove 17 can be kept constant without reducing the groove cross-sectional shape thereof, and good oil circulation can be secured, and sufficient oil can be supplied to the thrust washer 14 surface.

In the above-described embodiment, the case where the end of the pinion shaft 6 is fixed to the carrier plate 3 by the pin 10 is taken as an example. However, the present invention is not limited to this. The present invention can be applied to a case where the portion is fixed to the carrier plate 3 by caulking.

Further, in the above-described embodiment, the case where one oil discharge groove 17 having a substantially V shape is formed is taken as an example. However, the present invention is not limited to this, and two or more oil discharge grooves 17 may be formed. Good.
Further, in the above-described embodiment, the oil discharge groove 17 is formed in a substantially V-shape so as to move away from the pin 10 toward the outer peripheral portion of the carrier plate 3, but it is not always necessary to do so. The oil discharge groove 17 may be formed in parallel with the oil discharge groove 10.

Next, an end lubrication structure for a pinion shaft of a planetary gear according to an embodiment of the present invention will be described with reference to FIGS. Note that the same parts as those in the above embodiment will be described using the same reference numerals.

In this embodiment, sufficient oil is supplied from the inner peripheral sides of the carrier plates 2 and 3 to the end of the pinion shaft 6 via the oil inflow groove 20 to provide the pinion shaft 6, the thrust washer 14, and the needle bearing. 4 and the carrier plates 2, 3, etc., are prevented from burning due to sliding heat.

More specifically, of the two thrust washers 14 externally inserted at the end of the pinion shaft 6, through holes 4a are respectively formed in the seating surfaces of the carrier plates 2 and 3 facing the axially outer thrust washers 14. , 4b are formed by pressing or cutting a substantially V-shaped oil inflow groove 20 extending from the inner peripheral edge of the carrier plate 2, 3 to the inner peripheral edge of the carrier plate 2, 3, thereby utilizing the centrifugal force caused by the rotation of the carrier 1. Thus, the oil is introduced from the inner peripheral sides of the carrier plates 2 and 3 to the end of the pinion shaft 6 through the oil inflow groove 20.

As shown in FIG. 6, a pin 10 is disposed at the center of the V-shape of the oil inflow groove 20 formed on the seating surface of the carrier plate 3 so that the oil inflow groove 20
Are not overlapped with the pins 10 in the thickness direction of the carrier plate 3.

Further, in this embodiment, the seating surfaces of the carrier plates 2 and 3 facing the thrust washer 14 are provided.
A substantially V-shaped oil discharge groove 1 extending from the inner peripheral edges of the through holes 4a, 4b toward the outer peripheral edges of the carrier plates 2, 3 respectively.
7, whereby the oil flowing from the oil inflow groove 20 to the end of the pinion shaft 6 is applied to the outer peripheral side of the carrier plates 2 and 3 through the oil discharge groove 17 by using the centrifugal force of the rotation of the carrier 1. It is guided and discharged to the outside.

The pin 10 is arranged at the center of the V-shape of the oil discharge groove 17 formed on the seating surface of the carrier plate 3, so that the oil discharge groove 17 extends in the thickness direction of the carrier plate 3. It does not overlap with the pin 10.

In the lubricating structure of the end portion of the pinion shaft of the planetary gear having the above-described structure, the inner peripheral side of the carrier plate 2, 3 from the end portion of the pinion shaft 6 to the seat surface facing the thrust washer 14 of the carrier plate 2, 3. A substantially V-shaped oil inflow groove 20 formed so as to expand toward
Since the carrier plates 2 and 3 and the pinion shaft 6 are arranged obliquely so as to gradually move away from the center line S in the radial direction, the inflow efficiency at the time of inflow of oil using the centrifugal force of the rotation of the carrier 1 is improved. Can be achieved.

The oil discharge grooves 17 also extend toward the outer peripheral sides of the carrier plates 2 and 3.
Also, since the pinion shaft 6 is formed obliquely so as to gradually move away from each radial center line S, the oil flowing from the oil inflow groove 20 is discharged by using the centrifugal force generated by the rotation of the carrier 1. Efficiency can be improved.

Further, the oil inflow groove 20 is provided on the carrier plate 3.
So that it does not overlap with the pin 10 in the thickness direction of
As in the related art, it is possible to prevent the tip of the pin 10 from jumping into the oil inflow groove 20 when the pin is driven, and to secure a sufficient pressure input.

Further, since the oil discharge groove 17 is also prevented from overlapping the pin 10 in the thickness direction of the carrier plate 3, the carrier plate 3 is pressed when the pin 10 is press-fitted from the outer peripheral side of the carrier plate 3. Even if it is a thin plate formed by processing or the like, a sufficient press-fit width can be obtained.

Further, the oil discharge groove 17 is connected to the carrier plate 3.
By arranging the oil discharge groove 17 so as not to overlap with the pin 10 in the thickness direction of the oil discharge groove 17, it is possible to reduce the bulging deformation of the oil discharge groove 17 when the oil discharge groove 17 is pressed from the groove bottom side when the pin 10 is pressed. Thereby, the oil discharge groove 17 can be kept constant without reducing the groove cross-sectional shape, and good oil discharge can be ensured.

In the above embodiment, the case where the end of the pinion shaft 6 is fixed to the carrier plate 3 by the pin 10 is taken as an example. However, the present invention is not limited to this. The present invention can be applied to a case where the portion is fixed to the carrier plate 3 by caulking.

In the above-described embodiment, the case where one oil inflow groove 20 having a substantially V-shape is formed is taken as an example. However, the present invention is not limited to this, and two or more oil inflow grooves 20 may be formed. Good.

[0056]

As is apparent from the above description, in the first aspect of the present invention, since the oil discharge groove is formed in the bearing surface of the carrier plate facing the washer, the end of the pinion shaft is lubricated. In this case, the effect that the durability of the washer can be improved can be obtained.

According to the second aspect of the present invention, in addition to the first aspect, the oil inflow groove is formed obliquely toward the outer peripheral side so as to gradually move away from the radial center lines of the carrier plate and the pinion shaft. Therefore, the effect is obtained that the efficiency of discharging oil can be improved by utilizing the centrifugal force caused by the rotation of the carrier.

According to the third aspect of the present invention, in addition to the first or second aspect, the oil discharge groove does not overlap with the pin in the thickness direction of the carrier plate. Even if it is a thin plate formed by press working or the like, an effect that a sufficient press-fitting width can be obtained can be obtained.

Further, since the oil discharge groove does not overlap the pin in the thickness direction of the carrier plate, the oil discharge groove is not deformed when the oil discharge groove is pressed from the groove bottom side when the pin is press-fitted. Can be reduced, and as a result
The oil cross-sectional shape of the oil discharge groove is kept constant without being reduced, so that good oil circulation can be ensured, and an effect that sufficient oil can be supplied to the washer surface can be obtained.

According to the fourth aspect of the present invention, the carrier plate and the pinion shaft have an oil inflow groove formed on the bearing surface of the carrier plate facing the washer so as to extend from the end of the pinion shaft toward the inner peripheral side of the carrier plate. Are arranged obliquely so as to gradually move away from the respective radial center lines, so that the effect of improving the inflow efficiency when inflowing oil using centrifugal force due to the rotation of the carrier can be obtained. .

According to a fifth aspect of the present invention, in addition to the fourth aspect of the present invention, the oil discharge groove is also gradually moved away from the radial center lines of the carrier plate and the pinion shaft toward the outer peripheral side of the carrier plate. Since it is formed obliquely, an effect is obtained that the efficiency of discharging the oil flowing from the oil inflow groove by using the centrifugal force of the rotation of the carrier can be improved.

According to the sixth aspect of the invention, in addition to the fourth or fifth aspect, the oil inflow groove does not overlap the pin in the thickness direction of the carrier plate. It is possible to prevent the tip of the pin from jumping out into the oil inflow groove, and it is possible to obtain an effect that a sufficient pressure input can be secured.

[Brief description of the drawings]

FIG. 1 is an explanatory cross-sectional view for explaining an end lubrication structure of a pinion shaft of a planetary gear which is an example of an embodiment of the present invention.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is a view as seen from the direction of arrow B in FIG. 2;

FIG. 4 is a sectional view taken along line CC of FIG. 1;

FIG. 5 is an explanatory view for explaining an end lubrication structure of a pinion shaft of a planetary gear, which is an example of the embodiment of the fourth invention.

FIG. 6 is an explanatory diagram for explaining an oil inflow groove formed in a carrier plate on a pin press-in side;

FIG. 7 is an explanatory diagram for explaining a conventional end lubrication structure of a pinion shaft of a planetary gear.

FIG. 8 is an overall perspective view of a washer in which an oil discharge groove is formed.

FIG. 9 is an explanatory view for explaining an end lubrication structure of a pinion shaft of another conventional planetary gear.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Carrier 2, 3 ... Carrier plate 6 ... Pinion shaft 7 ... Oil passage 8 ... Oil hole 10 ... Pin 12 ... Pinion 13 ... Needle bearing (bearing) 14 ... Thrust washer 17 ... Oil discharge groove 20 ... Oil inflow groove

Claims (6)

[Claims] 1. A pinion shaft having an end fixed to a carrier plate, a pinion rotatably supported by a bearing on the pinion shaft, and a pinion shaft which is rotatable between the pinion and the carrier plate. A planetary gear having an washer inserted therein and configured to supply oil to the bearing from an oil hole opened at a position facing the bearing of the pinion shaft, wherein the carrier plate has a bearing surface facing the washer. An end lubrication structure for a pinion shaft of a planetary gear, wherein an oil discharge groove extending from an end of the pinion shaft toward an outer peripheral side of the carrier plate is formed. 2. The pinion shaft of a planetary gear according to claim 1, wherein said oil discharge groove is formed in a substantially V-shape extending from an end of said pinion shaft toward an outer peripheral side of said carrier plate. End lubrication structure. 3. An end portion of the pinion shaft is fixed to the carrier plate by passing a pin press-fitted in a radial direction of the carrier plate from an outer peripheral side of the carrier plate in a radial direction of the pinion shaft. The oil discharge groove is formed at a position where the oil discharge groove does not overlap with the pin in the thickness direction of the carrier plate.
3. The end lubrication structure of the pinion shaft of the planetary gear according to 2 or 3. 4. A pinion shaft having an end fixed to a carrier plate, a pinion rotatably supported on the pinion shaft via a bearing, and an outer pinion shaft between the pinion and the carrier plate. A planetary gear having an washer inserted therein, and allowing the oil to flow into the end of the pinion shaft from the inner peripheral side of the carrier plate, wherein the pinion is provided on a bearing surface of the carrier plate facing the washer. An end lubrication structure for a pinion shaft of a planetary gear, wherein a substantially V-shaped oil inflow groove extending from an end of the shaft toward an inner peripheral side of the carrier plate is formed. 5. A substantially V-shaped oil discharge groove extending from an end of the pinion shaft toward an outer peripheral side of the carrier plate is formed on a seat surface of the carrier plate facing the washer. The end lubrication structure for a pinion shaft of a planetary gear according to claim 4, wherein 6. An end portion of the pinion shaft is fixed to the carrier plate by passing a pin press-fitted in a radial direction of the carrier plate from an outer peripheral side of the carrier plate in a radial direction of the pinion shaft. The oil inflow groove is formed at a position not overlapping with the pin in a thickness direction of the carrier plate.
6. The end lubrication structure for a pinion shaft of a planetary gear according to claim 5.