JP3089972B2 - Lubrication structure of one-way clutch - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lubricating structure for a one-way clutch, and more particularly to an improvement in a lubricating structure for guiding lubricating oil from a groove formed in an inner peripheral surface of an end bearing into the clutch. is there.

[0002]

2. Description of the Related Art One-way clutches are used in automatic transmissions for vehicles and the like. However, for the purpose of improving abrasion resistance during idling, the inside of the clutch, that is, the sprag receiving space sandwiched between a pair of end bearings. Usually, lubricating oil is supplied. For example, Shokai 5
The device described in JP-A-8-132258 is one example. The one-way clutch 10 shown in FIG. 6 is also an example, and the inner race 12 and the outer race 14 are arranged concentrically with the center line S, and a number of sprags 16 are arranged in an annular space between them. A pair of first end bearings 18a arranged and guided on both sides of the
And a second end bearing 18b, and lubricating oil is supplied directly into the clutch from an oil hole 20 provided in the inner race 12. The one-way clutch 10 is one component of an automatic transmission for a vehicle, and the inner race 12 is disposed so as to be rotatable relative to a shaft 22 and is integrally formed with a sun gear of a planetary gear device. The lubricating oil is guided to the oil hole 20 through an oil supply path 24 and an oil hole 26 provided in the oil hole 20. Although the sprag 16 shown in FIG. 6 has a cocoon shape, one-way clutches using balls, rollers, and the like are widely known.

[0003]

However, a large load is applied to the inner peripheral portion (rolling surface) of the sprag 16 in which the oil hole 20 is provided, when the sprag 16 is pressed when the clutch is engaged. If it is not preferable in terms of strength and a large transmission torque capacity is to be ensured, the size of the one-way clutch 10 must be increased. On the other hand, a spiral groove is formed on the inner peripheral surface of the end bearing so that lubricating oil is guided from the outside to the inside of the clutch by a pump action during relative rotation.
No. 8423 has been proposed. Therefore, when lubricating oil is supplied from the shaft 22 as shown in FIG. 6, for example, as shown in FIG. 7, an oil hole 30 is provided in an inner peripheral portion of one of the first end bearings 18a.
The oil hole 30 is formed on the inner peripheral surface of the first end bearing 18a.
If the oil groove 32 for guiding the lubricating oil supplied from the inside to the clutch is provided, the sprag 16 and the like can be lubricated without impairing the transmission torque.

By the way, in an automatic transmission for a vehicle,
Since the gears constituting the planetary gear device and the like are helical gears, a thrust load is applied, and the inner race and the outer race move relative to each other in the axial direction by the clearance of each part depending on the shift speed or the positive or negative of the torque. For this reason, when the oil hole 30 is provided only on the left side of the first end bearing 18a as shown in FIG. 7, the oil hole 30 is shifted to the left side of the first end bearing 18a by the relative movement in the axial direction. In some cases, the lubricating oil supplied from the oil hole 30 cannot be sufficiently introduced into the clutch. FIG. 8 shows that the inner race 12 relatively moves to the left in the drawing and the oil hole 30 is moved.
Is shifted outward from the end bearing 18a,
This shows a state in which lubricating oil cannot be introduced into the clutch.

The present invention has been made in view of the above circumstances, and an object of the present invention is to allow the inner race and the end bearing to move relative to each other in the axial direction without hindering an increase in the transmission torque. Another object of the present invention is to provide a good lubrication effect.

[0006]

In order to achieve the above object, according to the present invention, a sprag and end bearings disposed on both sides of the sprag are axially moved by a predetermined dimension with respect to an inner race. In the one-way clutch, lubricating oil supplied from an oil hole provided in the inner race so as to open to the outer peripheral surface of the inner race is guided to the inside of the clutch from an oil groove formed in the inner peripheral surface of the end bearing. A lubrication structure, wherein the oil hole and the oil groove communicate with each other regardless of the relative movement,
The oil hole and the oil groove are provided so that the oil hole is not located on the inner peripheral side of the sprag regardless of the relative movement.

[0007]

In the lubricating structure of such a one-way clutch, the oil hole and the oil groove can communicate with each other regardless of the relative movement between the inner race and the end bearing. Regardless, a good lubricating action is obtained, and the wear resistance is improved. Moreover, the oil hole is not located on the inner peripheral side of the sprag irrespective of the relative movement, so that the strength is not impaired, and the same as when the oil hole is provided on the inner peripheral side of the sprag. If the transmission torque capacity is sufficient, the one-way clutch can be downsized,
With a one-way clutch of the same size, it is possible to increase the capacity of the transmission torque.

The above is the operation and effect unique to the present invention. A preferred embodiment of the present invention is directed to a first embodiment in which lubricating oil is introduced to the inside of the clutch on the inner peripheral surfaces of both the first end bearing and the second end bearing. An oil groove and a second oil groove are provided, and the inner race has a first position at a position located on the inner peripheral side of the first end bearing when the inner race is relatively moved to the second end bearing side. An oil hole is provided, and a second oil hole is provided at a position located on the inner peripheral side of the second end bearing in a state where the inner race is relatively moved to the first end bearing side.
In this case, even when the axial length of the end bearing is smaller than the relative movement amount with respect to the inner race, the lubricating oil is guided from at least one of the paths, so that a good lubricating action can be reliably obtained. The first oil hole and the second oil hole are not located in the inner peripheral portion of the sprag. If the axial length of the end bearing is short and the amount of relative movement is large, communication between both oil holes and oil grooves may be interrupted during the relative movement. Since it is located at the relative movement end, even if lubricating oil is temporarily insufficiently introduced during the relative movement, poor lubrication does not occur.

On the other hand, when the axial length of the end bearing is larger than the relative movement amount and the oil hole can be always held at the inner peripheral side of the end bearing irrespective of the relative movement, the oil hole and the oil hole are not necessarily provided on both sides. There is no need to provide oil grooves. Further, the oil groove provided on the inner peripheral surface of the end bearing may have a spiral shape in which lubricating oil is fed into the inside of the clutch by a pump action at the time of relative rotation with the inner race. The lubricating oil supplied from the oil hole is guided to the inside of the clutch regardless of whether the end is closed or whether only a straight groove is formed in both sides in the axial direction in the axial direction. be able to. It is not always necessary that the inner race and the end bearing rotate relative to each other during idling, and the end bearing can be rotated relative to the outer race as long as the end bearing can be moved at least integrally with the outer race in the axial direction. May be.

The position of the oil hole formed in the inner race may be such that at least a portion opened to the outer peripheral surface of the inner race satisfies the above requirements. The opening position and the like can be set arbitrarily.

[0011]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a sectional view of an essential part showing an example of an automatic transmission for a vehicle provided with a lubricating structure for a one-way clutch according to the present invention, and FIG. 2 is an enlarged view of the one-way clutch. The one-way clutch 50 of the present embodiment has a cocoon-like shape that is disposed in the annular space between the inner race 12 and the outer race 14 and the annular space between the inner race 12 and the outer race 14. A first end bearing 52a disposed on the left and right sides of the sprag 16 in the same annular space as in the drawing;
And a second end bearing 52b. The one-way clutch 50 is one component of the automatic transmission for a vehicle, and
Are integrally formed with the sun gears 40 and 42 of the left and right planetary gear units 36 and 38 in FIG.
2, while being arranged so as to be relatively rotatable around the outer circumference thereof,
The outer race 14 is provided with the planetary gear units 36, 38.
And a brake hub member 48 which is selectively fixed to a transmission case 46 by a brake 44 disposed on the outer peripheral side of the vehicle.

The shaft 22 forms a hollow shaft, the hollow portion of which is the oil supply passage 24, and the plurality of oil holes 26 are provided so as to communicate from the oil supply passage 24 to the outer peripheral surface. Have been. For this reason, part of the lubricating oil sent into the oil supply passage 24 is
Is supplied to the outer peripheral side of the inner race 12, that is, the inner peripheral side of the inner race 12. The inner race 12 is also provided with an oil hole at an appropriate position so as to communicate from the inner peripheral surface to the outer peripheral surface, but a pair of first oil holes 54a exclusively for supplying lubricating oil to the one-way clutch 50 are provided. The second oil hole 54b is provided at a predetermined position in the axial direction so as to penetrate in the radial direction. The first oil hole 54a on the left side in the drawing is for supplying lubricating oil to the inner peripheral side of the first end bearing 52a, and the second oil hole 54b on the right side is for supplying the inner peripheral side of the second end bearing 52b. It is for supplying lubricating oil. As is apparent from FIG. 2, the first oil groove 56a and the second oil groove 5 are provided on the inner peripheral surfaces of the first end bearing 52a and the second end bearing 52b, respectively.
6b are formed respectively, and the pair of oil holes 54
The lubricating oil supplied through a and 54b is guided to the inside of the clutch, that is, to the sprag 16 side. These oil grooves 56a and 56b are formed in a spiral shape so as to feed the lubricating oil into the clutch by a pumping action, for example, at the time of relative rotation with the inner race 12, but the outer side in the axial direction (the side opposite to the sprag 16). May be formed in the axial direction, or a linear groove whose end is closed may be formed in the axial direction, or may be formed in the axial direction. The oil holes and oil grooves are provided at a plurality of positions in the circumferential direction as necessary.

In such an automatic transmission for a vehicle, a thrust load acts because the respective gears constituting the planetary gear units 36 and 38 are helical gears.
The inner race 12 and the outer race 14 are relatively moved in the axial direction by the clearance of each part depending on the shift speed or the sign of the torque. 1 and 2 show the inner race 1.
3 shows a state in which the outer race 14 has relatively moved to the leftmost side with respect to 2, while FIG. 3 shows a state in which the outer race 14 has relatively moved to the rightmost side with respect to the inner race 12. The sprag 16 and the end bearings 52a, 52
b is held by the outer race 14 via the pair of holding members 58a and 58b so as to be relatively immovable and relatively rotatable in the axial direction, and is moved relative to the inner race 12 together with the outer race 14, whereby the oil Hole 54
The positional relationship between the oil grooves 56a and 56b and the oil grooves 56a and 56b changes.

Here, the first oil hole 54a is formed so that the inner race 12 is relatively fixed to the second end bearing 5 as shown in FIG.
While being provided at a position located on the inner peripheral side of the first end bearing 52a in a state of being moved to the 2b side,
The second oil hole 54b is provided at a position located on the inner peripheral side of the second end bearing 52b when the inner race 12 is relatively moved to the first end bearing 52a side as shown in FIG. . In other words, the formation positions of the first oil hole 54a and the second oil hole 54b are respectively determined such that the sprags 16 on the outer peripheral surface of the inner race 12 deviate from both sides from the range in which the sprags 16 can contact by the relative movement. 2, the first oil hole 54a does not overlap with the inner peripheral side of the sprag 16 even in the state of FIG. 2, that is, in the state of being closest to the sprag 16, and the second oil hole 54b is Even in the state shown in FIG. 3, that is, in the state in which the sprag 16 is closest to the sprag 16, the sprag 16 does not overlap with the inner peripheral side. For this reason, the rolling surface (outer peripheral surface) of the inner race 12 against which the sprag 16 is pressed when the clutch is engaged is not impaired in strength, and is positioned on the inner peripheral side of the sprag 16 as shown in FIG. The durability is improved as compared with the case where the oil hole 20 is provided.

On the other hand, the lubricating action in such a lubricating structure will be described. In the state of FIG. 2, the second oil hole 54b is located outside the second end bearing 52b in the axial direction (right side in the figure).
In this case, the first oil hole 54
a supplied from the first end bearing 52a
Is guided to the first oil groove 56a to lubricate the inside of the one-way clutch 50. On the other hand, in the state of FIG.
4a is displaced to the outside of the first end bearing 52a in the axial direction (left side in the figure). In this case, the lubricating oil supplied from the second oil hole 54b is supplied to the second oil of the second end bearing 52b. Guided by the groove 56b, the inside of the one-way clutch 50 is lubricated. In a relative movement state (not shown) intermediate between FIG. 2 and FIG. 3, the first oil hole 54a
The second oil holes 54b are partially located on the inner peripheral side of the end bearing 52a, respectively, and the lubricating oil supplied from both the oil holes 54a and 54b is Guided to the oil grooves 56a and 56b, respectively, the inside of the one-way clutch 50 is lubricated. That is, regardless of the relative movement between the inner race 12 and the outer race 14, at least one of the first oil hole 54a and the first oil groove 56a and the second oil hole 54b and the second oil groove 56b are communicated, and the inside of the clutch is Good lubrication.

As described above, according to the lubrication structure of this embodiment,
Regardless of the relative movement between the inner race 12 and the outer race 14, that is, the end bearings 52a and 52b, the first
At least one of the oil hole 54a and the second oil hole 54b is communicated with the corresponding one of the first oil groove 56a and the second oil groove 56b, and is reliably connected to any one of the paths. Since the lubricating oil is guided to the lubricating oil, a good lubricating action is obtained irrespective of the relative movement, and the wear resistance is improved. Further, regardless of the relative movement, none of the oil holes 54a and 54b is located on the inner peripheral side of the sprag 16, so that the sprag 16 does not lose its strength.
Compared to the case where the oil hole 20 is provided so as to be located on the inner peripheral side of the one-way clutch 50, the one-way clutch 50 can be downsized if the same transmission torque capacity is required, while the transmission torque can be increased if the same size. Becomes

Particularly, in this embodiment, oil grooves 56a and 56b are formed in both end bearings 52a and 52b, and a pair of oil holes 54a and
4b, the end bearings 52a, 52
Even when the axial length of b is smaller than the amount of relative movement with the inner race 12, the oil holes 54a and 54b are located on the inner peripheral side of the sprag 16 while maintaining the communication state of one of the oil paths. It is possible to configure so as not to have.

If the axial lengths of the end bearings 52a and 52b are smaller than about 1/2 of the relative movement amount as compared with the lubricating structure of the illustrated embodiment, both oil holes 54a are in the middle of the relative movement. , 54b and the communication between the oil grooves 56a, 56b are cut off.
Since the end bearings 52a and 52b are usually located at either of the relative movement ends, even if lubricating oil is temporarily insufficient during the relative movement, poor lubrication does not occur. Even in this case, there is no problem.

Next, another embodiment of the present invention will be described. The one-way clutch 60 shown in FIG. 4 includes, instead of the end bearings 52a and 52b, a first end bearing 62a and a second end bearing 62b whose axial dimension is longer than a relative movement amount of the inner race 14 and the outer race 16. An oil groove 66 having an axial dimension longer than the first oil groove 56a is formed on the inner peripheral surface of the first end bearing 62a, while the first oil hole 54a is formed in the inner race 12. Oil hole 6 at the same position as
8 are provided. And the inner race 12 is the second
In FIG. 4 showing a state of relative movement to the end bearing 62b side, that is, the right side of the drawing, the lubricating oil supplied through the oil hole 68 enters the one-way clutch 60 through the oil groove 66 as in the above-described embodiment. It leads to a good lubrication action. In the state of FIG. 5 showing the state in which the inner race 12 has relatively moved to the first end bearing 62a side, that is, the left side of the figure, the oil groove 66 having a long axial dimension is positioned so as to overlap the oil hole 68. Therefore, a sufficient amount of lubricating oil is guided through the oil groove 66.

Also in this embodiment, good lubrication can be obtained irrespective of the relative movement between the inner race 12 and the end bearings 62a, 62b, and the oil hole 68 is located on the inner peripheral side of the sprag 16. Because there is no, the strength is not impaired, and the same effect as in the above-described embodiment can be obtained. In addition, in this embodiment, since only one set of the oil hole 68 and the oil groove 66 is required, there is an advantage that the processing cost can be reduced.

Although the embodiments of the present invention have been described in detail with reference to the drawings, the present invention can be embodied in other forms.

For example, while the oil holes 54a and the like in the above-described embodiment are formed individually (one) at predetermined positions, a large number of small holes are provided to form one oil hole 54a.
It is also possible to configure a and the like, and in that case, it is possible to suppress a decrease in strength at the oil hole portion.

In the embodiment shown in FIG. 4, the oil groove 66 having a long axial length is provided on one end bearing 62a side, while the oil groove 66 is provided on the other end bearing 62b side and the inner groove is provided. An oil hole 68 may be provided in the race 12 at the same position as the second oil hole 54b in the embodiment of FIG.

In the above embodiment, the lubricating structure for a one-way clutch according to the present invention is applied to an automatic transmission for a vehicle. However, the same applies to other mechanical devices having a one-way clutch for transmitting torque. The present invention may be applied to:

Although not specifically exemplified, the present invention can be implemented in various modified and improved modes based on the knowledge of those skilled in the art.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating a main part of an example of an automatic transmission for a vehicle having a lubricating structure for a one-way clutch according to the present invention.

FIG. 2 is a partially enlarged view showing the one-way clutch portion of FIG. 1 in an enlarged manner in detail.

FIG. 3 is a partially enlarged view showing a state in which an inner race relatively moves to a first end bearing side in the embodiment of FIG. 1;

FIG. 4 is a sectional view of a main part showing another embodiment of the present invention.

FIG. 5 is a sectional view showing a state in which the inner race has relatively moved to the first end bearing side in the embodiment of FIG. 4;

FIG. 6 is a diagram illustrating an example of a conventional one-way clutch lubrication structure.

FIG. 7 is a diagram illustrating a comparative example of a lubricating structure of a one-way clutch.

8 is a diagram showing an example of the lubrication structure shown in FIG.
It is a figure explaining the state where it relatively moved to the end bearing side.

[Explanation of symbols]

 12: inner race 14: outer race 16: sprag 50, 60: one-way clutch 52a, 62a: first end bearing 52b, 62b: second end bearing 54a: first oil hole 54b: second oil hole 56a: first oil groove 56b: Second oil groove 66: Oil groove 68: Oil hole

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-2-27861 (JP, A) JP-A-58-132258 (JP, U) JP-A-1-100949 (JP, U) JP-A-2- 103531 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) F16H 57/00-57/04 F16D 41/07

Claims (1)

(57) [Claims] 1. A one-way clutch in which a sprag and end bearings disposed on both sides of the sprag are axially moved by a predetermined dimension with respect to an inner race, wherein the sprag is opened to an outer peripheral surface of the inner race. A lubricating structure for guiding lubricating oil supplied from an oil hole provided in an inner race from an oil groove formed on an inner peripheral surface of the end bearing to the inside of the clutch, The oil groove and the oil groove are provided so as to be communicated with the oil groove, and such that the oil hole is not located on the inner peripheral side of the sprag regardless of the relative movement. One-way clutch lubrication structure.