JP2003028188A - Universal joint - Google Patents

Abstract

PROBLEM TO BE SOLVED: To surely prevent generation of abnormal noise due to interference between a spider shaft portion and a needle bearing and to reduce bending torque of a steering shaft without causing a rise in manufacturing cost, and to achieve smoothness. To get a good steering feeling. A needle bearing (5) is provided in a bearing hole (4) of a yoke (1).
, The spider shaft portion 6 is rotatably fitted. The vicinity of the bearing holes 4 of the yokes 1 and 2 is locally deformed so that the radial clearance of the needle bearing 5 is zero or substantially zero. Or, after the assembly of the joint is completed, the needle bearing 5
Is locally deformed to make the radial clearance of the needle bearing 5 zero or substantially zero.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a universal joint used in, for example, a vehicle steering system.

[0002]

2. Description of the Related Art In a vehicle steering system, for example, a pair of yokes and a cross-shaped spider are provided between an upper shaft and a lower shaft of a steering shaft, and torque is transmitted while rotating at a predetermined bending angle. A universal joint (cross shaft joint) is installed.

In the universal joint, the shaft portion of the spider is rotatably fitted in the bearing hole of the yoke via a full-roller type needle bearing. A minute gap (with play) may occur between the spider shaft part and the needle bearing, and when the vibration is transmitted from the wheel due to this minute gap (with play), noise may be generated due to interference between the two. is there.

In general, the precision of the bearing hole of the yoke, the spider shaft portion, and the needle bearing is improved, and if insufficient, selective fitting is performed to suppress backlash.

Further, in Japanese Patent Laid-Open No. 2000-170786, a spherical projection formed on the axis of the inner surface of the cup of the needle bearing is pressed against a conical hole formed on the axis of the spider shaft. As a result, the minute gap between the spider shaft portion and the needle bearing is uniformly maintained, and the generation of noise due to the interference between the two is prevented.

Further, in Japanese Utility Model Laid-Open No. 57-61228, a resin piece is press-fitted into a center hole formed in the shaft core of the spider shaft portion, and the movement is suppressed by the receiving shape of the bearing cup.

Further, in Japanese Patent Laid-Open No. 56-31528, a gap is locally provided in order to prevent excessive interference.

[0008]

However, in order to keep the rattling small by the precision of the parts, it is necessary to suppress the dimensional variation of each part to a fraction or less of the current condition, and the productivity is greatly increased. Lowers costs. Even so, depending on the combination, it will be over-screwed and there will be no rattling, but the bending torque of the joint will increase and the steering stability will decrease. Further, since the component parts are press-fitted in a state where the clearance of the bearing portion is zero or in the state of being crimped, galling is likely to occur and productivity is lowered. of course,
These problems can be solved by combining the proper shishiro, but since the selective fitting is performed, the productivity is greatly reduced.

Further, in Japanese Patent Application Laid-Open No. 2000-170786, the concentricity of the conical hole or the spherical projection is apt to be influenced, and if there are variations, the bending torque becomes large. Durability is also reduced due to the local slip fit. Since metal parts are also in contact with each other during assembly, accurate assembly is required and productivity is reduced.

Further, in Japanese Utility Model Laid-Open No. 57-61228, since the contact is made through a resin piece, accuracy is not required, but there is a limit in terms of durability and heat resistance.

Further, in Japanese Patent Laid-Open No. 56-31528, there is a case that the bearing is apt to move in the axial direction and the radial direction because a gap is formed between the bearing hole of the yoke and the outer surface of the bearing.

The present invention has been made in view of the above-mentioned circumstances, and reliably prevents the generation of abnormal noise due to the interference between the spider shaft portion and the needle bearing without increasing the manufacturing cost. At the same time, it is an object of the present invention to provide a universal joint that can reduce the bending torque of the steering shaft to obtain a smooth steering feeling.

[0013]

To achieve the above object, in a universal joint according to a first aspect of the present invention, a spider shaft portion is rotatably fitted in a bearing hole of a yoke via a needle bearing. In the above universal joint, the vicinity of the bearing hole of the yoke is locally deformed to make the radial clearance of the needle bearing zero or substantially zero.

Further, in the universal joint according to claim 2 of the present invention, in the universal joint in which the spider shaft portion is rotatably fitted in the bearing hole of the yoke via the needle bearing, the needle is assembled after the assembly is completed. The vicinity of the bearing is locally deformed to make the radial clearance of the needle bearing zero or substantially zero.

As described above, according to the present invention, among parts made with normal working accuracy, the vicinity of the bearing hole of the yoke is locally deformed, so that the needle bearing is inserted into the bearing hole of the yoke. When the spider shaft is press-fitted by pressing, the effect of local deformation will be proportional to the inner diameter side of the bearing hole of the yoke, so there will be almost no gap between the spider shaft, the bearing roller, and the bearing cup. It is zero and there is no rattling.

Since the deformation is a part of the periphery of the bearing hole, it causes local crimping in the circumferential direction and axial direction, and avoids an excessive crimping condition where there is no escape, so that an extreme increase in bending torque is also avoided. Even in terms of durability, the contact surfaces are all in contact with each other, so that wear is suppressed and bending torque is also prevented from increasing.

From the above, the same applies to the case where the vicinity of the needle bearing is locally deformed after the assembly of the joint is completed, and in the present invention, due to the interference between the spider shaft portion and the needle bearing, the manufacturing cost does not increase. It is possible to reliably prevent the generation of abnormal noise, and reduce the bending torque of the steering shaft to obtain a smooth steering feeling.

[0018]

BEST MODE FOR CARRYING OUT THE INVENTION A universal joint according to an embodiment of the present invention will be described below with reference to the drawings. (First Embodiment) FIG. 1 is a side view including a partially cutaway cross section of a universal joint according to a first embodiment of the present invention. 2A is a cross-sectional view taken along the line aa of FIG.
FIG. 1B is a sectional view taken along line bb of FIG. 1.

As shown in FIG. 1, in the universal joint, a cross-shaped spider 3 is interposed between a pair of yokes 1 and 2. A spider shaft portion 6 is rotatably fitted in a bearing hole 4 of the yoke 1 via a needle bearing 5, and a seal member 7 is provided around the lower outer periphery of the spider shaft portion 6.

An axial hole 8 is formed in the shaft core of the spider shaft portion 6, and the needle bearing 5 has a bearing hole 4 formed therein.
There is provided a bearing cup 9 made of a thin steel plate fitted to the inside of which a plurality of roller rolling elements 10 are arranged.

In the present embodiment, as shown in FIG. 2A, one or more locations are provided near the bearing holes 4 of the yokes 1 and 2 by punches (not shown) on each side from the inside of the yokes 1 and 2. The punch hole 11 is processed to locally deform a part of the bearing hole 4. As a result, the radial clearance of the needle bearing 5 is zero or substantially zero. The shape of the punch hole 11 is not limited to the conical shape and may be a long groove.

Further, as shown in FIG. 2 (b), punches (not shown) are provided near the bearing holes 4 of the yokes 1 and 2 at two or more punch holes 11 on each side from the inside of the yokes 1 and 2. May be processed.

As described above, according to the present embodiment, among the parts made with normal working accuracy, the vicinity of the bearing holes 4 of the yokes 1 and 2 is locally deformed, so that the yokes 1 and 2 are deformed.
When the spider shaft portion 6 is press-fitted into the bearing hole 4 of the spider shaft portion 5 via the needle bearing 5, the effect of local deformation is proportionally exerted on the inner diameter side of the bearing hole 4 of the yokes 1 and 2, and as a result, the spider shaft portion 6, There is little or no gap between the bearing roller 10 and the bearing cup 9, and there is no backlash.

Since the deformation is also a part of the periphery of the bearing hole 4,
Since it becomes a local interference in the circumferential direction and the axial direction, and the excessive interference in which there is no escape can be avoided, an extreme increase in bending torque can also be avoided. Even in terms of durability, the contact surfaces are all in contact with each other, so that wear is suppressed and bending torque is also prevented from increasing.

Also in terms of heat resistance, there is no effect because the material of the constituent parts is steel. Furthermore, in the assembly
The initial fitting state between the end of the shaft portion 6 and the bearing 5 is originally prone to galling due to misalignment or the like. On the other hand, if the fitting is performed by interference fitting in order to suppress the backlash, it becomes more likely to cause galling. Therefore, in the present embodiment, since the normal fitting clearance is obtained in the initial fitting state of the spider shaft portion 6 and the bearing 5, the assembly can be performed normally. Only in the stable state in the latter half of the fitting, there is no adverse effect on the assembling work because the fitting is done by the local deformation. Further, in this embodiment, since the play is eliminated by the local deformation, the coaxiality of the bearing with respect to the cross shaft is not easily affected, and the deterioration of the sealing property and the increase of the bending torque can be suppressed.

From the above, in the present embodiment, 1) a stable universal joint or a universal joint close to rattle zero can be obtained, 2) a stable universal joint with a low bending torque can be obtained, and 3) conflicts. A universal joint that achieves both zero play and low bending torque can be obtained. 4) No additional machining equipment is required for the yokes 1 and 2, so there is no need for extensive machining equipment and high productivity. , Low cost, 5) assembly is the same as before, high productivity and low cost, 6) no heat deterioration, 7) sufficient durability, initial performance is maintained. In a real vehicle, vibration is suppressed. In addition, the responsiveness when traveling straight ahead is secured. Further, it is possible to suppress the generation of abnormal noise when traveling on a rough road. (Second Embodiment) FIG. 3A is a side view of a universal joint according to a second embodiment of the present invention, and FIG. 3B is an axial sectional view thereof.

In the present embodiment, after the joint assembly is completed,
Two punch holes 11 are formed by punches (not shown) in the same direction as the four bearing slip-off preventing caulks (12), whereby the bearing cup 9 is deformed inward, and the shaft portion 6
The gap between and is reduced or eliminated. Other configurations
The operation is similar to that of the first embodiment.

In the illustrated example, the punch hole 1 is provided from the outer peripheral side.
Although 1 is machined, the punch hole 11 may be machined from the inner peripheral side after the assembly is completed. (Third Embodiment) FIG. 4A is a perspective view of a universal joint according to a third embodiment of the present invention, and FIG. 4B is a sectional view thereof.

In this embodiment, a part (13) around the inner hole of the bearing hole 4 is pressed by a press or the like to be shallowly and widely deformed. As a result, the bearing cup 9 is deformed inward, and the gap with the shaft portion 6 is reduced or eliminated. Other configurations and operations are similar to those of the first embodiment. (Fourth Embodiment) FIG. 5 is a sectional view of a universal joint according to a fourth embodiment of the present invention.

In the above-described first embodiment (FIG. 2 (b)), two or more punch holes 11 are formed near the bearing hole 4 on each side from the inside of the yokes 1 and 2.
In the present embodiment, two or more punch holes 11 are formed on each side from the outside of the yokes 1 and 2. In this case, the punching work is simple. Other configurations
The operation is similar to that of the first embodiment.

The present invention is not limited to the above-described embodiments, but can be modified in various ways.

[0032]

As described above, according to the present invention,
Among parts made with normal processing accuracy, the vicinity of the bearing hole of the yoke is locally deformed.Therefore, if the spider shaft is press-fitted into the bearing hole of the yoke via the needle bearing, the local deformation will occur. As a result of the influence proportionally to the inner diameter side of the bearing hole of the yoke, there is almost no clearance or zero clearance between the spider shaft portion, the bearing roller, and the bearing cup, and rattling does not occur.

Since the deformation is also a part of the periphery of the bearing hole, it causes local crimping in the circumferential direction and the axial direction and avoids an excessive crimping state where there is no escape, so that an extreme increase in bending torque is also avoided. Even in terms of durability, the contact surfaces are all in contact with each other, so that wear is suppressed and bending torque is also prevented from increasing.

From the above, the same applies to the case where the vicinity of the needle bearing is locally deformed after the assembly of the joint is completed. In the present invention, due to the interference between the spider shaft portion and the needle bearing, the manufacturing cost does not increase. It is possible to reliably prevent the generation of abnormal noise, and reduce the bending torque of the steering shaft to obtain a smooth steering feeling.

[Brief description of drawings]

FIG. 1 is a side view including a partially cutaway cross section of a universal joint according to a first embodiment of the present invention.

2A is a sectional view taken along line aa in FIG. 1, and FIG. 2B is a sectional view taken along line bb in FIG.

FIG. 3 (a) is a side view of a universal joint according to a second embodiment of the present invention, and FIG. 3 (b) is an axial sectional view thereof.

4A is a perspective view of a universal joint according to a third embodiment of the present invention, and FIG. 4B is a sectional view thereof.

FIG. 5 is a sectional view of a universal joint according to a fourth embodiment of the present invention.

[Explanation of symbols]

1, 2 yoke 3 spider 4 bearing holes 5 Needle bearing 6 Spider shaft 7 Seal member 8 Axial hole 9 Bearing cup 10 Rolling elements 11 punch holes 12 Caulking for preventing bearing loss 13 Press points

Claims (2)

[Claims] 1. In a universal joint in which a spider shaft portion is rotatably fitted in a bearing hole of a yoke via a needle bearing, the vicinity of the bearing hole of the yoke is locally deformed to provide a radial direction of the needle bearing. A universal joint characterized in that the clearance is zero or substantially zero. 2. A universal joint in which a spider shaft portion is rotatably fitted in a bearing hole of a yoke via a needle bearing, and after assembly of the joint is completed, the vicinity of the needle bearing is locally deformed to form a needle. A universal joint characterized in that the radial clearance of the bearing is zero or substantially zero.