JP3471117B2 - Pinion shaft lubrication structure - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pinion shaft lubrication structure in which oil is introduced from one end surface of a pinion shaft fixed to a pinion carrier by using a pin member or a snap ring and is allowed to flow out to a cylindrical surface.

[0002]

2. Description of the Related Art Automatic transmissions using a planetary gear device are widely used. The planetary gear device has a plurality of pinion gears arranged in the space between the central sun gear and the surrounding ring gear,
A planetary motion of a pinion gear around the sun gear. The pinion shafts (rotating shafts) of the plurality of pinion gears are fixed to a common pinion carrier by using a pin member such as a spring pin or a snap ring. The pinion gear is
It is rotatably attached to each pinion shaft.

In an automatic transmission using a planetary gear device, in the process of guiding the lubricating oil supplied from the center side to the outer peripheral side, the tooth surface of the planetary gear device, the bearing structure, etc., each of which requires lubrication and cooling. Flow into the place. Lubricating oil involved in lubrication and cooling flows down along the inner wall of the housing of the automatic transmission and is collected in the oil pan on the bottom side. The oil accumulated in the oil pan is pressurized by an oil pump built into the automatic transmission, returned to the center side of the automatic transmission through an oil cooler for heat removal, and recirculated. The pinion shaft lubrication structure is a structure in which the lubricating oil is guided to the outer peripheral side through the bearing structure of the pinion gear. The pinion shaft lubrication structure has a vertical hole oil passage that is formed in the axial direction and communicates with one side of the pinion shaft, and a horizontal hole oil passage that penetrates the vertical hole oil passage and reaches the cylindrical surface of the pinion shaft. The oil flows in from one end surface of the pinion shaft and flows out from the cylindrical surface.

A pinion shaft lubrication structure is disclosed in, for example, Japanese Utility Model Laid-Open No. 60-112747. here,
Lubricating oil is supplied from the main shaft oil passage arranged at the center of the main shaft (sun gear) of the automatic transmission, and part of the oil is part of one of the pinion shafts while being driven by centrifugal force to reach the inner wall surface of the housing. It flows in from the side and flows out to the cylindrical surface of the pinion shaft. Specifically, a radiant oil passage that penetrates the pinion carrier in the radial direction is provided, and an oil for lubrication from the main spindle oil passage to the radiant oil passage of the pinion carrier is provided through an outflow hole provided in the cylindrical surface of the main spindle. Is delivered. The radiation oil passage of the pinion carrier communicates with the vertical hole oil passage of the pinion shaft, and the lubricating oil flows out from the vertical hole oil passage of the pinion shaft to the cylindrical surface through the horizontal hole oil passage.

[0005]

[Problems to be Solved by the Invention]
In the pinion shaft lubrication structure disclosed in Japanese Patent Publication No. 47, since the vertical hole oil passage is arranged at the center of the cross section of the pinion shaft, in the case of a structure in which the pinion shaft is fixed to the pinion carrier by using a pin or snap ring, There is a possibility that the vertical oil passage interferes with the hole or the snap ring groove, causing a problem. For example, if the vertical hole oil passage communicates with the pin hole or the snap ring groove, the oil in the vertical hole oil passage will leak out through the pin hole or the snap ring groove, and the oil that flows out from the horizontal hole oil passage to the cylindrical surface will leak. Insufficient lubrication will result.
On the other hand, in order to prevent such oil leakage, it is possible to use a solid press-fitting pin or to narrow the width of the snap ring groove to hold the snap ring tightly. However, in this case, the work of assembling the pinion shaft to the pinion carrier becomes more difficult, and the assembly time and assembly cost of the automatic transmission increase.

If the pin hole or the snap ring groove intersects the vertical hole oil passage of the pinion shaft, a large stress concentration occurs around the pin hole or the snap ring groove, and the pinion shaft is substantially bent. Strength and fatigue strength decrease. Increasing the strength of the material used for the pinion shaft to deal with this increases the material cost and processing cost of the pinion shaft. Further, the low fatigue strength makes it difficult to reduce the diameter of the pinion shaft, and becomes a factor that hinders the downsizing and weight reduction of the entire planetary gear device.

According to the present invention, the pin hole or the snap ring groove does not interfere with the vertical oil passage of the pinion shaft, and even if the deep pin hole or the snap ring groove is provided, the fatigue strength of the pinion shaft is not significantly impaired. It is intended to provide a shaft lubrication structure.

[0008]

According to a first aspect of the present invention, there is provided a pinion shaft lubrication structure in which oil is introduced from one end surface of a pinion shaft fixed to a pinion carrier by using a pin member and outflowed from a cylindrical surface. A vertical hole oil passage that is formed axially in the pinion shaft and communicates with one side of the pinion shaft, and a horizontal hole oil passage that penetrates the vertical hole oil passage and reaches the cylindrical surface. The vertical hole oil passage is eccentrically arranged on the cross section of the pinion shaft to the side opposite to the side on which the pin member is inserted, and the insertion hole of the pin member formed in the pinion shaft is the vertical hole oil passage. It does not penetrate all the way.

According to the second aspect of the present invention, there is provided a pinion shaft lubrication structure in which oil is introduced from one end surface of a plurality of pinion shafts fixed to a pinion carrier by using one snap ring and is made to flow out from a cylindrical surface. A vertical hole oil passage that is formed axially in the pinion shaft and communicates with one side of the pinion shaft; and a horizontal hole oil passage that penetrates the vertical hole oil passage and reaches the cylindrical surface,
The vertical hole oil passage is arranged eccentrically to the side opposite to the side where the snap ring is fitted in the cross section of the pinion shaft, and the snap ring groove formed in the pinion shaft penetrates to the vertical hole oil passage. Is something that is not.

According to a third aspect of the present invention, in the structure according to the first or second aspect, the formation of the vertical hole oil passage is stopped at a position where it does not reach the other end face of the pinion shaft, and it does not penetrate axially. Is.

[0011]

In the pinion shaft lubrication structure according to claim 1, since the insertion hole of the pin member is not communicated with the vertical hole oil passage,
Even when a hollow, axially transparent pin member is fitted into the insertion hole, the oil in the vertical oil passage does not leak to the outside through the insertion hole. Also, since the vertical oil passage is biased to the opposite side of the insertion hole, a deep insertion hole can be formed when viewed from the diameter of the pinion shaft, and even if the pinion shaft diameter is small, a sufficient insertion depth of the pin member can be achieved. Can be secured. Also, because the insertion hole of the pin member does not reach the vertical oil passage and the wall thickness increases on the insertion hole side, the insertion hole is arranged compared to the case where the vertical oil passage is arranged at the center of the cross section. The stress distribution on the cross section becomes gentle. In addition, the "portion where the vertical hole oil passage intersects with the insertion hole" where stress concentration is remarkable when the vertical hole oil passage is arranged at the center of the cross section and communicated with the insertion hole is eliminated. At the same time, the difference in bending strength between the cross-section where the insertion hole is arranged and the part where the insertion hole is not arranged is reduced, and the stress concentration in the axial direction is also alleviated. This increases the fatigue strength of the pinion shaft.

In the pinion shaft lubrication structure of claim 2, since the snap ring groove does not communicate with the vertical hole oil passage,
The oil in the vertical oil passage does not leak outside through the snap ring groove. Further, since the vertical hole oil passage is biased to the opposite side of the snap ring groove, a deep snap ring groove can be formed as viewed from the diameter of the pinion shaft, and a sufficient fitting depth of the snap ring with respect to the pinion shaft can be secured.

In the pinion shaft lubricating structure according to the third aspect of the present invention, oil does not leak from the vertical hole oil passage to the other side of the pinion shaft even if the vertical hole oil passage on the other side of the pinion shaft is not provided with a plug. The oil flowing into the vertical hole oil passage is efficiently guided to the horizontal hole oil passage and flows out to the cylindrical surface.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The pinion shaft lubrication structure of the first embodiment will be described with reference to FIGS. FIG. 1 is an explanatory view of a pinion shaft lubrication structure of the first embodiment, and FIG. 2 is a partial sectional view of an FF type automatic transmission. In FIG. 1, (a) is a cross section in the axial direction of the pinion shaft, (b) is a cross section perpendicular to the axial direction of the pinion shaft, and (c) is an FF of the pinion shaft.
It is in a state of being incorporated in the automatic transmission.

In FIG. 1A, a vertical hole oil passage 23 is formed along the center line of the pinion shaft 14. The vertical hole oil passage 23 does not penetrate the pinion shaft 14 in the axial direction, and the drilling is stopped at a position slightly beyond the horizontal hole oil passage 24. A pin hole 25 is formed in the cylindrical surface of the pinion shaft 14 on the opening side of the vertical hole oil passage 23. Pin hole 2
5 reaches a position beyond the center of the pinion shaft 14 as shown in (b), but the vertical hole oil passage 23 is arranged so as to be biased to the opposite side of the pin hole 25 in the cross section of the pinion shaft 14. Therefore, it does not communicate with the vertical hole oil passage 23.

In FIG. 1 (c), the pinion shaft 14 rotatably supports the pinion gear 13. Oil for lubrication is supplied to the bearing structure of the pinion gear 13 arranged between the pinion shaft 14 and the pinion gear 13 through a lateral hole oil passage 24 provided in the pinion shaft 14 as indicated by an arrow. The pinion shaft 14 is fixed to the pinion carrier 12 by using a spring pin 22. A pin hole is also formed in the pinion carrier 12 so as to correspond to the pin hole 25 of the pinion shaft 14, and the spring pin 22 is inserted with both (pin holes) aligned.

The side of the pinion shaft 14 on which the pin hole 25 is formed is inserted into the shaft hole formed on the pinion carrier 12. The shaft hole is formed in a stepped structure by expanding the diameter from the middle of the pilot hole, and the end of the pinion shaft 14 is abutted against the shoulder of the step. Since the bottom wall surface of the shaft hole (lower hole) located on the main shaft 17 side of the automatic transmission is partially removed, the bottom of the shaft hole communicates with the outer wall surface (left side in the figure) of the pinion carrier 12. ing. The unremoved part of the bottom of the shaft hole forms a bag-shaped oil reservoir 21, and the lubricating oil supplied from the main shaft 17 side of the automatic transmission and guided to the outer peripheral side by the centrifugal force is the oil. The reservoir 21 is filled, and the vertical hole oil passage 2 of the pinion shaft 14 is indicated by the arrow.
Inflow to 3.

A spindle oil passage 27 is formed by penetrating the center of the spindle 17 in the axial direction. The main oil passage 27 is supplied with lubricating oil whose pressure is increased by an oil pump (not shown) incorporated in the automatic transmission. The hydraulic cylinder 11 is fixed to the main shaft 17, and an oil hole 17H is formed adjacent to the mounting portion of the hydraulic cylinder 11. The hydraulic cylinder 11 rotates integrally with the main shaft 17. A spring retainer 15 is attached to the stepped portion of the inner cylinder surface of the hydraulic cylinder 11. The spring retainer 15 receives a reaction force of a return spring (not shown) (a reaction force of the return spring urging the piston toward the bottom side of the hydraulic cylinder 11) and is pressed against the adjacent snap ring 15S, whereby the spring retainer 15 moves in the axial direction. It is positioned at a fixed position.

Snap ring 15 of hydraulic cylinder 11
An oil hole 11H is formed at a position adjacent to S. The lubricating oil flowing out from the oil hole 17H of the main shaft 17 is
Oil hole 11 of hydraulic cylinder 11 driven by centrifugal force
It flows out from H as shown by the arrow, and is partly captured by the oil sump 21 through scattering and flowing.

In FIG. 2, the mechanical portion shown in FIG. 1C is stored in the housing of an automatic transmission which is constructed by connecting a side cover 52 to a transmission case 51. The side cover 52 is connected to the transmission case 51 by a plurality of connection bolts 53 arranged along the edge of the side cover 52. The spline 12S formed on the outer periphery of the left side portion of the pinion carrier 12 in the drawing constitutes a part of the clutch 54. On the other hand, the spline member 19 that is connected to the outside of the pinion carrier 12 and extends toward the right side in the drawing rotates together with the pinion carrier 12, and at the same time, one of the brakes 56 arranged on the outer peripheral portion inside the transmission case 51. Make up the department.

The planetary gear unit 57 includes an outer ring gear 1
8 and the inner sun gear 16 between the plurality of pinion gears 13
Place and mesh with each other. The pinion gear 13 is
It is rotatably supported by the pinion shaft 14 and makes a planetary motion around the sun gear 16. The oil supplied from the center side of the automatic transmission and guided to the outer peripheral side, and in the process of lubricating and cooling the planetary gear device 57, the clutch 54, the brake 56, and other necessary places, reaches the transmission case 51 and The oil flows down along the inner wall surface and is collected in an oil pan (not shown) connected to the bottom of the transmission case 51. The oil collected in the oil pan is increased in pressure by the above-mentioned oil pump incorporated in the automatic transmission and is removed from heat by an oil cooler (not shown). It is recirculated to the path 27.

According to the pinion shaft lubrication structure of the first embodiment, since the spring pin 22 is used as the pin member, assembling and re-disassembling of the planetary gear device 57 is performed as compared with the case of using the solid press-fitting pin. Will be easier. Also,
Since the vertical oil passage 23 is biased to the opposite side of the pin hole 25, the holding length of the spring pin 22 by the pin hole 25 can be sufficiently held. Therefore, the specifications of the pin hole 25 and the spring pin 22 may vary, and the pinion shaft 1
Even if a shock is applied to the 4 or pinion carrier 12,
There is no concern that the spring pin 22 will fall out. Further, since the pin hole 25 is not communicated with the vertical hole oil passage 23, oil leaks from the vertical hole oil passage 23 through the pin hole 25 even though the hollow and axially plain spring pin 22 is used. Don't worry.

Further, since the pin hole 25 is not communicated with the vertical hole oil passage 23, there is no intersection between the vertical hole oil passage 23 and the pin hole 25, and at the same time, the vertical hole oil passage 23 is provided on the opposite side of the pin hole 25. Since the wall thickness surrounding the vertical hole oil passage 23 is increased by increasing the thickness on the pin hole 25 side, the stress distribution in the cross section in which the pin hole 25 is provided becomes gentle, and the degree of stress concentration seen in the axial direction is also eased. There is. Therefore, even though the deep pin hole 25 is provided, the fatigue strength of the pinion shaft 14 is maintained, and even if the pinion shaft 14 is made thin or the material strength is reduced, the strength and life of the pinion shaft 14 are sufficient. Can be secured. Moreover, since the drilling of the vertical hole oil passage 23 is stopped midway and it does not penetrate the pinion shaft 14, all the lubricating oil that has flowed into the vertical hole oil passage 23 does not penetrate the vertical hole oil passage 23. Guided by the bearing structure of the pinion gear 13 through the passage 24, sufficient lubrication of the bearing structure can be ensured.

In the first embodiment, a spring pin having a C-shaped cross section and passing through in the axial direction is used as the pin member, but other types of spring pins or solid press-fit pins may be used. Further, the depth of the vertical hole oil passage 23 and the arrangement and number of the horizontal hole oil passages 24 can be freely changed. For example, a configuration may be adopted in which a blind plug is provided in a vertical hole oil passage that penetrates the pinion shaft 14.

A second embodiment will be described with reference to FIG. Here, a snap ring 42 is used instead of the pin 25 of the first embodiment. In FIG. 3, (a) is a cross section in the axial direction of the pinion shaft, (b) is an AA cross section perpendicular to the axial direction of the pinion shaft, and (c) is a state in which the pinion shaft is incorporated in a planetary gear device.

In FIG. 3A, a vertical hole oil passage 43 is formed along the center line of the pinion shaft 34. The vertical hole oil passage 43 does not penetrate the pinion shaft 34 in the axial direction, and the drilling is stopped at a position slightly beyond the horizontal hole oil passage 44. A snap ring groove 45 is formed on the cylindrical surface of the pinion shaft 34 on the opening side of the vertical hole oil passage 43. As shown in (b), the snap ring groove 45 crosses the cross section of the pinion shaft 14 at a considerably deep position to reduce the cross-sectional area in a half-moon shape, but the vertical hole oil passage 23 is provided on the opposite side of the snap ring groove 45. Since they are arranged so as to be uneven, the sufficient thickness is secured around the vertical hole oil passage 23.

In FIG. 3C, the three pinion gears 3 are provided between the outer ring gear 38 and the central sun gear 36.
3 is arranged. The pinion gear 33 is rotatably supported by a pinion carrier similar to that of the first embodiment using a pinion shaft 34, and makes a planetary motion around the sun gear 36. In the first embodiment, a spring pin is used, but in the second embodiment, a common snap ring 42 concentrically arranged with the sun gear 36 is used to lock the rotation of the three pinion shafts 34 to a pinion carrier (not shown). ing. The revolving motion of the pinion gear 33 with respect to the sun gear 36 is taken out through a common pinion carrier (not shown).

On the pinion carrier (not shown), an annular snap ring groove is formed around the outer circumference in correspondence with the axial position of the spring pin 22 shown in FIG. 1 (c). The snap ring 42 held in the snap ring groove is fitted into the snap ring grooves 45 of the three pinion shafts 34 to axially restrain the three pinion shafts 34 and, at the same time, to rotate each of them with respect to the pinion carrier. Make impossible. Snap ring 42
Is guided by the snap ring groove of the pinion carrier in a state where the mating surface 42A is widened against the elasticity of the whole and the inner diameter is increased, and the diameter is reduced by the elasticity of the whole to fit into the snap ring groove.

According to the pinion shaft lubrication structure of the second embodiment, as compared with the case where the vertical hole oil passage 43 is arranged at the center of the cross section of the pinion shaft 34, the pinion shaft 34
The snap ring groove 45 can be formed in a deep position.
Therefore, even if the snap ring 42 has a small diameter reducing ability (soft), the rotation of the pinion shaft 34 can be sufficiently restrained. In other words, the pinion shaft 34 rotates, the snap ring 42 is disengaged from the snap ring groove 45, and the pinion shaft 34 that has lost the axial restraint is unlikely to fall out of the pinion carrier.

Further, the snap ring groove 4 is provided in the vertical hole oil passage 43.
5, the vertical oil passage 43 and the snap ring groove 45 do not interfere with each other.
Since a sufficient wall thickness is secured between the two, the stress concentration at the bottom of the snap ring groove 45 is relieved, and the fatigue strength of the pinion shaft is not significantly impaired even though the deep snap ring groove 45 is provided. . Further, since the vertical hole oil passage 43 does not penetrate the pinion shaft 14, it is not necessary to provide a blind plug.

[0031]

According to the invention of claim 1, since the insertion hole of the spring pin is not communicated with the vertical oil passage, the oil in the vertical oil passage does not flow out through the insertion hole. In addition, since the vertical hole oil passage is biased to the opposite side of the insertion hole and the wall thickness surrounding the vertical hole oil passage is increased on the insertion hole side, in the cross section perpendicular to the axial direction in which the insertion hole is provided and in the axial direction. The stress concentration at the position is relaxed, and even if a deep insertion hole is formed, the fatigue strength of the pinion shaft is not significantly impaired. Therefore, even if the material strength is reduced and the material cost and the processing cost are reduced, the sufficient strength and life of the pinion shaft can be secured. It is also possible to reduce the diameter of the pinion shaft and design the entire device in a small size.

According to the second aspect of the present invention, since the plurality of pinion shafts are fixed by the common snap ring, the assembling work of the automatic transmission becomes easier as compared with the case of individually pinning. Further, since the snap ring groove does not communicate with the vertical hole oil passage, oil in the vertical hole oil passage does not flow out through the snap ring groove. In addition, the vertical hole oil passage is biased to the opposite side of the snap ring groove, and the wall thickness surrounding the vertical hole oil passage is increased on the side of the snap ring groove, so even if a deep snap ring groove is provided, the fatigue strength of the pinion shaft is increased. Can be sufficiently secured. Therefore, it is possible to reduce the material strength to reduce the material cost and the processing cost, and to reduce the diameter of the pinion shaft to design the entire apparatus in a small size.

According to the third aspect of the present invention, it is not necessary to provide a blind plug in the vertical oil passage, and the material cost and the processing cost of the pinion shaft can be reduced as compared with the case where the blind plug is provided.

[Brief description of drawings]

FIG. 1 is an explanatory diagram of a pinion shaft lubricating structure according to a first embodiment.

FIG. 2 is an explanatory diagram of a partial structure of an automatic transmission.

FIG. 3 is an explanatory diagram of a pinion shaft lubrication structure of a second embodiment.

[Explanation of symbols]

11 hydraulic cylinder 12 pinion carriers 13, 33 pinion gear 14,34 pinion shaft 15 Spring retainer 17 spindle 16,36 Sun gear 18, 38 ring gear 19 Spline members 21 oil sump 22 Spring pin 23,43 Vertical oil passage 24,44 Horizontal oil passage 25, 45 pin hole 27 Spindle oil passage 42 snap ring 51 transmission case 52 Side cover 53 Connection bolt 54 clutch 56 brakes 57 Planetary gear unit 11H, 17H oil hole 12S spline 15S snap ring 42A mating surface

Continuation of the front page (56) Reference JP-A-2-51648 (JP, A) JP-A-7-301293 (JP, A) JP-A-2-248747 (JP, A) Actual development Sho-62-49052 (JP , U) Actually open 58-163749 (JP, U) Actually open 5-34350 (JP, U) Actually open 6-8858 (JP, U) Actually open 5-64560 (JP, U) (58) Fields surveyed (Int.Cl. ⁷ , DB name) F16H 57/00-57/12

Claims (3)

(57) [Claims] 1. A pinion shaft lubrication structure that allows oil to flow in from one end surface of a pinion shaft fixed to a pinion carrier by using a pin member and to flow out from a cylindrical surface, the axial structure being formed in the pinion shaft. And a vertical hole oil passage that communicates with one side of the pinion shaft, and a horizontal hole oil passage that penetrates the vertical hole oil passage and reaches the cylindrical surface, wherein the vertical hole oil passage includes the pinion shaft. In the cross section of the pin member, the pin member is eccentrically arranged on the side opposite to the side where the pin member is inserted, and the pin member insertion hole formed in the pinion shaft does not penetrate to the vertical hole oil passage. Pinion shaft lubrication structure. 2. A pinion shaft lubrication structure for allowing oil to flow in from one end surface of a plurality of pinion shafts fixed to a pinion carrier by using one snap ring and to flow out from a cylindrical surface, wherein: A vertical hole oil passage that is formed in the axial direction and communicates with one side of the pinion shaft, and a horizontal hole oil passage that penetrates the vertical hole oil passage and reaches the cylindrical surface. Is eccentrically arranged in a cross section of the pinion shaft to the side opposite to the side where the snap ring is fitted, and the snap ring groove formed in the pinion shaft does not penetrate to the vertical hole oil passage. With a pinion shaft lubrication structure. 3. The vertical hole oil passage is stopped from forming at a position that does not reach the other end surface of the pinion shaft, and does not penetrate in the axial direction.
The described pinion shaft lubrication structure.