JP2003120894A - Bearing lubrication structure of rotary shaft - Google Patents

Abstract

PROBLEM TO BE SOLVED: To use a supply passage for lubricating oil supplied to a first bearing (bearing 13) and a second bearing (bearing 14) in common. SOLUTION: In a lubrication structure in which lubricating oil is supplied from an oil passage 23 provided in a rotor shaft 8 or a rotary shaft 9 into a spline fitting part 22 constituted by fitting a male spline 20 formed on the rotor shaft 8 supported on the bearing 13 and a female spline 21 formed on the rotary shaft 14 supported on the bearing 14 mutually to lubricate the bearings 13, 14 using the lubricating oil flowing out of the spline fitting part 22, an oil chamber 25 which is nipped by the bearings 13, 14 and in which the lubricating oil flowing out of the spline fitting part 22 flows is partitioned among a housing supporting the bearings 13, 14, the rotor shaft 8, and the rotary shaft 9, and an oil sump 26 is formed on an inner peripheral face of the housing 24 constituting the oil chamber 25.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bearing lubrication structure for a rotary shaft.

[0002]

2. Description of the Related Art Two power transmission shafts may be coaxially spline-fitted to each other.
In Japanese Patent No. 21520, lubricating oil is supplied to a spline fitting portion via an oil passage provided in the spline female shaft, and the lubricating oil that lubricates the spline fitting portion supports the spline female shaft. A shaft coupling device for a high-speed rotating portion used for lubricating a bearing is disclosed.

[0003]

However, in the shaft connecting device disclosed in Japanese Unexamined Patent Publication No. 8-21520, the first bearing supporting the spline male shaft is provided with an oil passage provided in the spline female shaft. There is a problem that the lubricating oil is not supplied and a lubricating path for supplying the lubricating oil to the first bearing must be provided in addition to the lubricating path for supplying the lubricating oil to the second bearing supporting the spline female shaft. is there.

[0004]

Therefore, according to the invention described in claim 1, a male spline formed on a first rotating shaft supported by a first bearing and a second rotating shaft supported by a second bearing are provided. The female spline formed in the above is fitted to a spline fitting portion, and lubricating oil is supplied from an oil passage provided in the first rotating shaft or the second rotating shaft, and the spline fitting portion is supplied. In a lubricating structure that lubricates the first bearing and the second bearing by using the lubricating oil that has flowed out, a housing that supports the first bearing and the second bearing, the first rotating shaft, and the second rotating shaft are provided. An oil chamber, which is sandwiched between the first rotary bearing and the second rotary bearing and into which the lubricating oil flowing out from the spline fitting portion flows, is defined, and an inner circumference of the housing that constitutes the oil chamber is defined. Store a predetermined amount of lubricating oil on the surface It is characterized in that the oil reservoir is formed. As a result, the lubricating oil flowing into the oil chamber from the spline fitting is temporarily stored in the oil reservoir provided in the housing. Further, since the first bearing and the second bearing are arranged on both sides of the oil sump, the lubricating oil overflowing from the oil sump is supplied to the first rotary bearing and the second rotary bearing.

According to a second aspect of the present invention, in the first aspect of the present invention, the first rotary shaft is formed in a substantially stepped shape in the oil chamber, and the first rotary shaft has the tooth bottom surface of the female spline more than the tooth bottom surface. It is characterized in that it has a step surface that rises to the outer peripheral side in the radial direction of the first rotation shaft. As a result, when the lubricating oil is vigorously ejected from the spline fitting portion toward the oil chamber along the axial direction of the first rotating shaft and the second rotating shaft, the lubricating oil collides with the step surface.

According to a third aspect of the present invention, in the second aspect of the invention, the oil sump extends from the inner peripheral surface of the housing along the radial direction of the first rotary shaft and the second rotary shaft. While having a pair of wall portions that stand up and face each other, and lubricating oil is stored between the pair of wall portions, the pair of wall portions includes the first rotation shaft and the first rotation shaft of the pair of wall portions. It is characterized in that the position along the axial direction of the two rotation shafts is formed outside the opening end of the second rotation shaft located in the step surface and the oil chamber. The lubricating oil flowing from the spline fitting portion to the oil chamber flows from the gap between the step surface and the opening end of the second rotating shaft to the outer peripheral side in the radial direction of the first rotating shaft and the second rotating shaft. As a result, the lubricating oil flowing out from the spline fitting portion into the oil chamber is easily received by the oil reservoir.

According to a fourth aspect of the present invention, in the invention according to any one of the first to third aspects, the pair of wall portions are formed at the same height, and each of the pair of wall portions is formed. Is characterized in that a notch is provided at the tip of the. As a result, the lubricating oil in the oil reservoir flows through the notch and is supplied to the first bearing or the second bearing.

According to a fifth aspect of the invention, in the invention according to any one of the first to third aspects, the pair of wall portions are formed at the same height, and the pair of wall portions have the same height. ,
It is characterized in that through holes for discharging the lubricating oil stored in the oil reservoir are formed respectively. As a result, the lubricating oil in the oil sump flows through the through hole and is supplied to the first bearing or the second bearing.

According to a sixth aspect of the present invention, in the invention according to any one of the first to fifth aspects, the pair of wall portions of the oil sump have the first bearing, the second bearing and the housing. It is characterized by being composed of a pair of metal members sandwiched between. As a result, it is not necessary to form the inner peripheral surface of the housing into a complicated shape to form the oil sump.

[0010]

According to the present invention, the lubricating oil is temporarily stored in the oil reservoir provided in the housing, and the lubricating oil in the oil reservoir is supplied to the first rotary bearing and the second rotary bearing. The lubricating oil can be stably supplied to both the first bearing and the second bearing. In other words, a situation in which the lubricating oil is sometimes supplied to only one of the first bearing and the second bearing due to variations in the direction in which the lubricating oil is ejected from the spline fitting portion to the oil chamber and due to scattering Can be reliably prevented.

According to the second aspect of the present invention, the step surface is formed even if the lubricating oil is vigorously ejected from the spline fitting portion toward the oil chamber along the axial direction of the first rotating shaft and the second rotating shaft. Since it collides with the lubricating oil, the lubricating oil can be reliably guided to the oil reservoir, and the lubricating oil can be stably supplied to the first bearing and the second bearing.

According to the third aspect of the present invention, even if the lubricating oil flowing from the spline fitting portion into the oil chamber is scattered by the centrifugal force, the lubricating oil can be more reliably guided to the oil sump.

According to the inventions of claims 4 and 5, the supply amount of the lubricating oil supplied to the first bearing and the second bearing can be adjusted by the notch or the through hole, so that the first bearing can be adjusted. Even if the amount of lubricating oil required for the first bearing and the amount of lubricating oil required for the second bearing are different,
An appropriate amount of lubricating oil can be distributed and supplied to the bearing and the second bearing.

According to the invention of claim 5, it is not necessary to form the inner peripheral surface of the housing into a complicated shape in order to form the oil sump, so that the manufacturing cost can be reduced.

[0015]

DETAILED DESCRIPTION OF THE INVENTION An embodiment of the present invention will be described in detail below with reference to the drawings. FIG. 1 is an explanatory diagram of the overall configuration of a hybrid system 1 to which the lubricating structure of the first embodiment of the present invention is applied.

In this hybrid system 1, an engine 2 directly drives a generator 3, and a crankshaft 5 supported by a cylinder block 4 of the engine 2, a crankshaft 5 and a rigid body. A flywheel 6 connected thereto, a generator 3 to which a rotational force is applied by the engine 2, a motor 7 driven by electricity generated by the generator 3, and a rotor shaft 8 of the motor 7.
A gear 10 having a rotary shaft 9 that is spline-coupled with a differential gear 11 to which the rotational driving force of the motor 7 is transmitted via the gear 10 is roughly configured.

The rotor shaft 8 has bearings 12, 13
The gear 10 is supported by bearings 14 and 15.

Reference numeral 16 is a generator 3, a motor 7, and a gear 1.
It is a hybrid transmission case (hereinafter referred to as case 16) that accommodates 0 and the differential gear 11.

FIG. 2 corresponds to the portion A of FIG. 1 and shows the essential portion of the first embodiment of the present invention.

A male spline 20 is formed on the rotor shaft 8 as the first rotating shaft, and a female spline 21 which is fitted to the male spline 20 is formed on the rotating shaft 9 of the gear 10 as the second rotating shaft. ing.

Lubricating oil is supplied to the spline fitting portion 22 formed by fitting the male spline 20 and the female spline 21 from an oil passage 23 formed in the male spline 20.

The oil passage 23 also has a function of cooling the rotor shaft 8 itself, and the bearing 1 of the rotor shaft 8 is also included.
Lubricating oil is injected from the end on the second side. That is, the oil passage 23 is formed continuously over substantially the entire axial length of the rotor shaft 8.

Rotor shaft 8 on which male spline 20 is formed
The bearing 13 that supports one end of the rotary shaft 9 and the bearing 14 that supports one end of the rotary shaft 9 on which the female spline 21 is formed are supported by a housing 24 rigidly coupled to the case 16.

Here, the bearing 13 corresponds to the first bearing, and the bearing 14 corresponds to the second bearing. The bearing 13 and the bearing 14 are so-called ball bearings.
The housing 24 is manufactured by casting an aluminum alloy.

Housing 2 for supporting the bearings 13, 14
An oil chamber 25 sandwiched between the bearing 13 and the bearing 14 is defined between the inner peripheral surface of the rotor 4, the outer peripheral surface of the rotor shaft 8 and the outer peripheral surface of the rotary shaft 9.

The oil chamber 25 communicates with the spline fitting portion 22 and is constructed so that the lubricating oil that lubricates the spline fitting portion 22 flows in.

The housing 2 forming the oil chamber 25
An oil reservoir 26 that stores a predetermined amount of lubricating oil is formed on the inner circumferential surface of the housing 4 over the entire circumference of the inner circumferential surface of the housing 24.

The oil sump 26 is formed in the housing 24.
Has a pair of wall portions 27 and 28 that rise from the inner peripheral surface of the rotor along the radial direction of the rotor shaft 8 and the rotating shaft 9 and face each other. A predetermined amount of lubricating oil is stored between the pair of wall portions 27 and 28. Has been done. The pair of wall portions 27, 28 are formed to have the same height as each other. In other words, the respective wall portions 27, 2 on the radially inner side of the rotor shaft 8 and the rotary shaft 9
The inner diameters of the eight tips are formed to be the same.

Auxiliary member 29 fixed to the housing 24
Is sealed between the outer peripheral surface of the rotor shaft 8 by the annular seal member 30. A first drain flow path 31 is defined between the housing 24 and the seal member 30 and the auxiliary member 29 into which the lubricating oil that lubricates the bearing 13 flows.

The first drain passage 31 is connected to the housing 2
The second drain passage 32 formed in the inside of the housing 4 communicates with the drain chamber 33 outside the housing.

The spline fitting portion 22 is lubricated and the rotating shaft 9
Although the lubricating oil flowing out from the open end 34 of the oil chamber 25 to the oil chamber 25 is scattered by the centrifugal force generated by the rotation of the rotor shaft 8 and the rotating shaft 9, as shown by the arrow in the figure, the oil pool 26 on the inner peripheral surface of the housing 24 Once collected. Then, the oil sump 26 is filled with the lubricating oil in a relatively short time, and the lubricating oil that has passed over the pair of wall portions 27 and 28 is located on both sides of the oil sump 26 as shown by the arrow in the figure. Bearing 13,
14 are supplied.

The lubricating oil that has lubricated the bearing 13 flows into the drain chamber via the first drain passage and the second drain passage as shown by the arrow in the figure. On the other hand, the lubricating oil that has lubricated the bearing 14 directly flows into the drain chamber 33 as shown by the arrow in the figure.

In the first embodiment constructed as described above, the oil chamber 25 located on the downstream side of the spline fitting portion 22.
Since the lubricating oil is supplied to the bearings 13 and 14 from the oil reservoir 26 in the inside, it is necessary to separately provide a supply path for supplying the lubricating oil to the bearing 13 and a supply path for supplying the lubricating oil to the bearing 14. Therefore, the lubricating structure for supplying the lubricating oil to the bearings 13 and 14 can be downsized as a whole.

Further, the lubricating oil overflows from the oil sump 26, and the lubricating oil that has passed over the pair of wall portions 27 and 28 is supplied to the bearings 13 and 14. Therefore, the amount of lubricating oil supplied to the bearings 13 and 14 is increased. From the spline fitting part 22 to the oil chamber 2
It is possible to reliably prevent a situation where the lubricating oil is sometimes supplied to only one of the bearings 13 and 14 due to variations in the direction of the lubricating oil flowing out to the bearing 5 and the consequences of the scattering. Bearing 1 by
It is possible to reliably prevent the deterioration of the durability of Nos. 3 and 14.

The amount of lubricating oil passing through the spline fitting portion 22 is not small at all, but by cutting off some of the teeth of the male spline 20 or the teeth of the female spline 21 as necessary, the spline fitting can be performed. The amount of lubricating oil passing through the junction 22 may be increased.

If the first drain passage 31 and the second drain passage 32 can be formed, the housing 2
4 and the auxiliary member 29 may be integrally formed.

Different embodiments of the present invention will be described below. In addition, the parts having the same configurations as those of the first embodiment described above,
The same reference numerals as those in the first embodiment are given and the duplicated description is omitted.

FIG. 3 shows a main part of the lubricating structure in the second embodiment of the present invention, and corresponds to the A part of the hybrid system 1 shown in FIG.

The second embodiment has substantially the same structure as the above-described first embodiment, but the rotor shaft 8 is formed in a substantially stepped shape in the oil chamber 25, and the tooth bottom surface of the female spline 21 is formed. Has a step surface 40 that rises to the outer peripheral side in the radial direction of the rotor shaft 8.

By doing so, the lubricating oil flowing out of the spline fitting portion 22 becomes a so-called water gun state due to the gap of the spline fitting portion 22 and the hydraulic pressure for supplying the lubricating oil, and the rotor shaft 8 and the rotating shaft 9 are Even if the initial speed is given in the axial direction and the oil is discharged, the lubricating oil once hits the step surface 40 and the axial speeds of the rotor shaft 8 and the rotary shaft 9 are erased, and the oil pool 26 is more reliably retained by the centrifugal force. Lubricating oil can be stored. That is, the lubricating oil can be reliably guided to the oil sump 26, and the lubricating oil can be stably supplied to the bearings 13 and 14.

FIG. 4 shows the essential parts of the lubricating structure in the third embodiment of the present invention, and corresponds to the A part of the hybrid system 1 shown in FIG.

In the third embodiment, in the second embodiment described above, the position of the pair of wall portions 27, 28 along the axial direction of the rotor shaft 8 and the rotary shaft 9 is the step surface 40 and the oil chamber 25. Is formed so as to be located outside the position of the open end 34 of the rotating shaft 9 located along the axial direction of the rotor shaft 8 and the rotating shaft 9.

In other words, the opening 45 defined by the opening end 34 and the step surface 40 is formed inside the pair of wall portions 27 and 28.

In the third embodiment, the lubricating oil flowing out from the opening end 34 of the rotary shaft 9 into the oil chamber 25 via the spline fitting portion 22 is sprung out by the centrifugal force, that is, the opening position. The position of 45 corresponds to the pair of wall portions 27, 28.
Since they are located inside the positions of the rotor shaft 8 and the rotating shaft 9 along the axial direction, even if the lubricating oil is scattered by the centrifugal force, the lubricating oil can be more reliably received by the oil sump.

FIG. 5 shows a lubricating structure according to the fourth embodiment of the present invention, which corresponds to the portion A of the hybrid system 1 shown in FIG.

The fourth embodiment is different from the above-described second embodiment in that notches 50 and 51 are provided at the tips of the pair of walls 27 and 28, respectively. The notches 50 are provided at predetermined intervals along the circumferential direction of the wall 27, and the notches 51 are provided at predetermined intervals along the circumferential direction of the wall 28.

Each notch 50 along the circumferential direction of the wall 27 ...
The notch width of 50 and the notch depth of each notch portion 50 ... 50 along the radial direction of the rotor shaft 8 and the rotating shaft 9 are appropriately set. Similarly, each notch 5 along the circumferential direction of the wall 28
The cutout widths of 1 ... 51 and the cutout depths of the cutout portions 51 ... 51 along the radial direction of the rotor shaft 8 and the rotary shaft 9 are set appropriately.

In the fourth embodiment, the lubricating oil stored in the oil sump 26 flows out from the notches 50 and 51 to both sides of the oil sump 26. That is, the notch width and notch depth of each notch portion 50 ... 50 and each notch portion 51 ...
By appropriately setting the notch width and the notch depth of 51, the supply amount of the lubricating oil supplied from the notches 50 ... 50 to the bearing 13 is adjusted, and the notches 51 ... 51 from the bearing 1
The supply amount of the lubricating oil supplied to No. 4 is adjusted.

More specifically, when the amounts of lubricating oil required for the bearings 13 and 14 are different from each other, the notches 50 ... 50
By appropriately setting the notch width and the notch depth of the notch parts 51, ...
It is possible to adjust the distribution ratio of the lubricating oil supplied to No. 4 to an appropriate amount.

In the fourth embodiment, the plurality of notches 50 and 51 are provided in the pair of wall portions 27 and 28, respectively, but one notch is provided in each of the pair of wall portions 27 and 28. The parts 50 and 51 may be formed.

Since the lubricating oil stored in the oil sump tends to accumulate vertically downward (downward in FIG. 5) due to gravity, the notches 50 and 51 should be concentratedly formed downward in FIG. You may

FIG. 6 shows a main part of a lubricating structure according to the fifth embodiment of the present invention, which corresponds to the part A of the hybrid system 1 shown in FIG.

In the fifth embodiment, the through holes 55 and 56 are formed in the pair of wall portions 27 and 28, respectively, in the second embodiment described above. A plurality of through holes 55 are provided at predetermined intervals along the circumferential direction of the wall portion 27, and a plurality of through holes 56 are provided at predetermined intervals along the circumferential direction of the wall portion 28.

In the fifth embodiment, since the lubricating oil is supplied from the oil sump 26 to the bearings 13 and 14 through the through holes 55 ... 55 and the through holes 56 ... 56, the through holes 55 ... By appropriately setting the diameters of 55 and the through holes 56 ... 56, it becomes possible to adjust the distribution ratio of the lubricating oil supplied from the oil sump 26 to the bearings 13 and 14 to an appropriate amount.

Since the lubricating oil stored in the oil reservoir 26 tends to accumulate vertically downward (downward in FIG. 6) due to gravity, the through holes 55 ... 55 and the through holes 56 ... 56.
May be intensively formed on the lower side in FIG.

Further, as described above, in the first to fifth embodiments, the oil sump 26 is formed on the entire circumference of the inner peripheral surface of the housing 24, but the lubricating oil in the oil chamber 25 is vertically downward due to gravity. In consideration of the tendency to accumulate on the side, the pair of wall portions 27, 2 is provided only on the vertically lower side of the inner peripheral surface of the housing 24.
8 may be provided, and the oil sump 26 may be formed only on the vertically lower side of the housing 24.

FIG. 7 shows a main part of the lubricating structure in the sixth embodiment of the present invention, and corresponds to the A part of the hybrid system 1 shown in FIG.

In the sixth embodiment, an iron washer 60 as a metal member sandwiched between the bearing 13 and the housing 24 and an iron washer 6 as a metal member sandwiched between the bearing 14 and the housing 24 are provided.
1 and the inner peripheral surface of the housing 24 form an oil sump 26.

Usually, the housing 24 is cast from aluminum in consideration of mass productivity. On the other hand, the bearings 13, 1
Since 4 is made of iron, iron washers 60, 61 are sandwiched between the bearings 13, 14 and the housing 24.

Therefore, in the sixth embodiment, the pair of washers 60 and 61 are used to form the pair of wall portions 2 described above.
7, 28 constitute an oil sump 26.

In the sixth embodiment as described above, the pair of wall portions 27 and 28 of the oil sump 26 are connected to the pair of washers 6.
By using 0,61, the manufacturing cost can be reduced.

The pair of wall portions 27 of the oil sump 26,
As a pair of metal materials forming 28, the bearings 13,
It may be a shim used for finely adjusting the positions of the rotor shaft 8 and the rotating shaft 9 along the axial direction.

Further, in each of the above-described embodiments, the male spline 20 is formed on the rotor shaft 8 of the motor 7 and the female spline 21 is formed on the rotary shaft 9 of the gear 10. However, the female spline is formed on the rotor shaft 8. May be formed to form a male spline on the rotary shaft 9.

[Brief description of drawings]

FIG. 1 is an explanatory diagram of the overall configuration of a hybrid system.

FIG. 2 is an enlarged view of part A of FIG. 1, showing an essential part of a bearing lubrication structure for a rotary shaft according to a first embodiment of the present invention.

FIG. 3 is an enlarged view of part A of FIG. 1, showing an essential part of a bearing lubrication structure for a rotating shaft according to a second embodiment of the present invention.

FIG. 4 is an enlarged view of part A of FIG. 1, showing an essential part of a bearing lubrication structure for a rotating shaft according to a third embodiment of the present invention.

FIG. 5 is an enlarged view of part A of FIG. 1, showing an essential part of a bearing lubrication structure for a rotating shaft according to a fourth embodiment of the present invention.

FIG. 6 is an enlarged view of part A of FIG. 1, showing an essential part of a bearing lubrication structure for a rotating shaft according to a fifth embodiment of the present invention.

FIG. 7 is an enlarged view of part A of FIG. 1, showing an essential part of a bearing lubrication structure for a rotating shaft according to a sixth embodiment of the present invention.

[Explanation of symbols]

8 ... Rotor shaft 9 ... Rotary axis 13 ... Bearing (first bearing) 14 ... Bearing (second bearing) 22 ... Spline fitting part 24 ... Housing 25 ... Oil chamber 26 ... Oil sump 27 ... Wall 28 ... Wall 31 ... First drain passage 32 ... Second drain passage

   ─────────────────────────────────────────────────── ─── Continued front page    F term (reference) 3J101 AA02 AA42 AA52 AA62 AA82                       BA77 CA05 CA08 CA13 CA14                       FA32 GA21 GA24

Claims (6)

[Claims] 1. A male spline formed on a first rotary shaft supported by a first bearing, and a second spline supported by a second bearing.
Lubricating oil is supplied from an oil passage provided in the first rotating shaft or the second rotating shaft to a spline fitting portion formed by fitting a female spline formed on the rotating shaft, and the spline fitting is performed. In a lubrication structure for lubricating the first bearing and the second bearing with the lubricating oil flowing out from the portion, a housing supporting the first bearing and the second bearing, the first rotating shaft, and the second rotating shaft. Between the first rotary bearing and the second rotary bearing, an oil chamber into which the lubricating oil flowing out from the spline fitting portion flows is defined, and between the housing and the housing forming the oil chamber. A bearing lubrication structure for a rotating shaft, wherein an oil reservoir for storing a predetermined amount of lubricating oil is formed on the inner peripheral surface. 2. The first rotating shaft is formed in a substantially stepped shape in the oil chamber, and has a step surface that rises from a tooth bottom surface of the female spline to a radially outer peripheral side of the first rotating shaft. The bearing lubrication structure for the rotating shaft according to claim 1, wherein 3. The oil sump has a pair of wall portions that stand up from the inner peripheral surface of the housing along the radial direction of the first rotating shaft and the second rotating shaft and face each other. Lubricating oil is stored between the portions, and the pair of wall portions have the step surface and the position of the pair of wall portions along the axial direction of the first rotating shaft and the second rotating shaft. The bearing lubrication structure for a rotating shaft according to claim 2, wherein the lubricating structure is formed outside the opening end of the second rotating shaft located in the oil chamber. 4. The pair of wall portions are formed at the same height as each other, and a notch is provided at each tip of the pair of wall portions. A bearing lubrication structure for a rotating shaft according to any one of the above. 5. The pair of wall portions are formed at the same height as each other, and the pair of wall portions are respectively formed with through holes for discharging the lubricating oil stored in the oil reservoir. The bearing lubrication structure for a rotating shaft according to any one of claims 1 to 3, characterized in that. 6. The pair of wall portions of the oil sump are
The bearing lubrication structure for a rotary shaft according to claim 1, comprising a pair of metal members sandwiched between the first bearing, the second bearing and the housing.