JP3657646B2 - One way clutch bush - Google Patents

Description

[0001]
[Industrial application fields]
The present invention relates to a one-way clutch bush used as a backstop in an automobile torque converter.
[0002]
[Prior art]
FIG. 1 is a sectional view showing an example of a torque converter, in which 1 is a plate for transmitting rotation of an engine (not shown) to the torque converter 2, 3 is a pump impeller of the torque converter 2, 4 is a turbine runner, A stator, 6 is an output shaft, 7 is a fixed shaft, 8 is an outer ring of the one-way clutch 10, 9 is an inner ring, 11 and 12 are bushes, and 20 and 21 are thrust needle bearings.
[0003]
The stator 5 is generally made by die casting of an aluminum alloy or synthetic resin injection molding, and the bushes 11 and 12 are generally made of an aluminum alloy or a high strength brass material.
[0004]
2 shows the relationship between a conventional bush and a thrust needle bearing. FIG. 2 (a) is a front view seen from the thrust surface side, and FIG. 2 (b) is a side sectional view of the assembly of the bush and thrust bearing. And 11a is a thrust surface which a thrust needle bearing contacts. A groove 11b through which lubricating oil flows is provided between the thrust surfaces. 11c is a groove | channel from which lubricating oil flows out from the inside of a one-way clutch. The lubricating oil flows as shown by an arrow R in FIG.
[0005]
As shown in FIG. 2B, the thrust needle bearing 20 is provided in contact with the thrust surface 11a. In the figure, 22 and 23 are needle races, and 24 is a needle.
[0006]
The thrust surface 11 a of the bush 11 serves as a backup for the thrust needle bearing 20. When the stator 5 rotates, the needle 24 rolls between the races 22 and 23 of the thrust needle bearing 20.
[0007]
【task to solve】
As described above, the thrust surface 11a of the bush 11 serves as a backup for the thrust needle bearing 20, but the thrust load generated from the stator 5 increases due to the high output of the engine. Then, because of the large load, the bush 11 is deformed in the axial direction as indicated by a broken line 25 in FIG.
[0008]
For this reason, when the backup function to the thrust needle bearing 20 is lowered, the needle 24 that is rolling between the races 22 and 23 is strongly contacted on the outer peripheral side. When the thrust surface 11a is inclined, the needle 23 tends to have a shorter life.
[0009]
FIG. 5 shows the relationship between the thrust load and the bush deformation amount, with the bush deformation amount Q (μm) on the vertical axis and the thrust load G (kgf) on the horizontal axis.
[0010]
Further, FIG. 6 shows the relationship between the inclination and the life of the needle as an experimental value by taking the life Ln (time) of the needle on the vertical axis and the inclination S (μm) of the thrust surface 11a on the horizontal axis. is there.
[0011]
Because of this tendency, when the thrust load is large, it is necessary to give the needle 24 special heat treatment or crowning, or increase the thickness of the needle race 22 to increase its rigidity. Further, the bush 11 must be made of a high-strength material in order to increase the rigidity, which is disadvantageous in terms of cost.
[0012]
[Means for Solving the Problems]
In order to solve the above-described problems, the present invention provides a bushing used as a back-up for a thrust needle bearing and a centering of outer and inner rings of a one-way clutch incorporated in a stator of a torque converter, and a thrust surface in contact with the thrust needle bearing of the bush Thus, a bush for a one-way clutch is obtained, which has a certain inclination that inclines toward the one-way clutch along the radial direction from the inner periphery to the outer periphery.
[0013]
【Example】
In the present invention, the amount of deformation of the bush shape due to the thrust load is ascertained from the actually measured values shown in FIGS. 5 and 6, and the rolling width B of the needle 23 is determined on the thrust surface 11a of the bush 11 as shown in FIG. The optimum slope A is set at the site.
[0014]
According to the present invention, when a large thrust load is generated on the thrust surface 11a and the bush 11 is deformed, the inclination of the thrust surface 11a provided in advance as described above is reduced and functions reliably as a backup for the thrust needle bearing 20.
[0015]
【effect】
In the present invention, by providing an inclination on the thrust surface of the bush, the needle rolls smoothly without impairing the backup function even if a large thrust load is generated.
[0016]
As a result, the measures taken for conventional needle bearings are no longer necessary, and the cost increase factor has been eliminated.
[Brief description of the drawings]
FIG. 1 is an explanatory diagram of the basic configuration of a torque converter. FIG. 2 (a) is a front view of a bush. FIG. 2 (b) is an assembly view of a bush and a needle bearer. FIG. 4 is a sectional side view of the bush of the present invention. FIG. 5 is a diagram showing the relationship between thrust load and bush deformation. FIG. 6 is a diagram showing the relationship between the inclination of the thrust surface and the life of the needle. Description】
DESCRIPTION OF SYMBOLS 1 Plate 2 Pump impeller 3 Pump impeller 4 Turbine runner 5 Stator 6 Output shaft 7 Fixed shaft 8 Outer ring 9 Inner ring 10 One-way clutch 11 Bush 11a Thrust surface 11b Groove 11c Groove 20 Thrust needle bearing 21 Thrust needle bearing 22 Race 23 Race 24

Claims (1)

In one-way clutch bushings used as a back-up for thrust needle bearings and centering of outer and inner rings of one-way clutches incorporated in the stator of the torque converter,
A bush for a one-way clutch, characterized in that a thrust surface that is in contact with the thrust needle bearing of the bush has a certain inclination that inclines toward the one-way clutch side along the radial direction from the inner peripheral side to the outer peripheral side.

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