JPH05141432A - Connecting structure for spline connecting portion - Google Patents

Abstract

PURPOSE:To prevent generation of a play so as to prevent generation of abrasion and abnormal noise in a connecting portion due to a play by achieving a stable tightened state at three points in a connecting structure for connecting an inner and an outer spline to each other. CONSTITUTION:The relationship between a thickness of a spline tooth of an inner spline portion and a thickness of a spline tooth of an outer spline portion is determined as follows: The thickness of a spline tooth in an arcuate portion extending on both sides in the circumferential direction by a predetermined length is formed into a large tooth thickness 21d, a middle tooth thickness 21e and a small tooth thickness 21f. Clearances between the teeth in the engaged portion of the splines before connection of the splines exist in portions of the small and middle tooth thicknesses 21f, 21e, where the clearance in the portion of the small tooth thickness 21f is larger than that in the portion of the middle tooth thickness 21e, while are made almost zero in the portion of the large tooth thickness 21d. Furthermore, a clearance between the tooth surfaces before and after the tooth thickness of each spline of the small and middle tooth thicknesses 21f, 21e becomes approximately equal to each other.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a connecting structure for a spline connecting portion of two connecting members.

[0002]

2. Description of the Related Art As one type of connecting structure of a spline connecting portion of two connecting members, a shaft-shaped first connecting member having an outer spline on the outer peripheral side and a cylindrical inner spline having an inner peripheral side are provided. At the same time, a second coupling member which can be reduced in diameter with respect to one point in the circumferential direction as a base point and which is fitted onto the first coupling member is used to reduce the diameter of the second coupling member. There is a coupling structure of a spline coupling part for spline coupling by tightening it upward. A joint structure which is an example of this type is shown in Japanese Utility Model Laid-Open No. 61-17373, and FIGS. 4 and 5 show cross sections showing the joint structure of the type.

In the coupling structure of the spline coupling portion of this type, as shown in these figures, the splines 1a and 2a of the coupling members 1 and 2 are formed to have the same tooth thickness. When the second connecting member 2 is tightened on the first connecting member 1, the splines 1a, 2a facing each other are configured to be engaged with each other almost completely, and the splines 1a, 2a are assembled with each other. There is a tooth surface gap in.

[0004]

By the way, in the coupling structure of this type, as described above, each spline 1
Since a and 2a are formed to have the same tooth thickness and a tooth surface gap is present, the fitting state of the second joining member 2 to the first joining member 1 before tightening is as shown in FIG. Become. That is, in the fitting state shown in FIG. 4, the first coupling member 1 is spline 1 on the side of the base point of diameter reduction due to its own weight.
The a and 2a mesh with each other with a small gap present, and mesh with each other such that the gap gradually increases as the distance from the base point increases. In addition, each such spline 1a,
In the meshed state of 2a, the tooth flank gaps δ1 and δ2 of the splines 1a and 2a have a very small tooth flank gap δ1 on the base point side and a large tooth flank gap δ2 on the opposite side.

Therefore, when both the flange portions 2b and 2c of the second coupling member 2 are tightened with the bolts 3a and the nuts 3b in this state as shown in FIG. 5, the second coupling member 2 becomes the first coupling member 1. Tightened on each spline 1a,
2a are substantially completely meshed with each other to form a spline connection, but due to this tightening, the parts A and B farthest from the base point side of the second connecting member 2 are largely deformed and tightened. As a result, the spline 2a of the second connecting member 2 bites into the spline 1a of the first connecting member 1, and the second connecting member 2 is deformed to the base point side by δ2.

For this reason, as shown in the figure, a large tooth surface gap is generated between the teeth of each spline on the base point side of the second connecting member 2, and the tightening with respect to the first connecting member 1 is A, B.
Since there are two parts of the part, the tightening cannot be achieved at the three parts which are in a stable tightened state, which causes backlash. As a result, when vibrations or the like are applied during use in a state in which the two coupling members 1 and 2 are spline-coupled to each other, the rattling causes wear at the coupling site and abnormal noise. Therefore, it is an object of the present invention to overcome these problems in this type of spline joint construction.

[0007]

According to the present invention, there is provided a shaft-shaped first coupling member having an outer spline on the outer peripheral side, a tubular shape having an inner spline on the inner peripheral side, and one point in the circumferential direction as a base point. And a second coupling member that can be reduced in diameter and is fitted onto the first coupling member by spline coupling by reducing the diameter of the second coupling member and tightening the second coupling member on the first coupling member. It is the connecting structure of the spline connecting part,
The spline characterized by setting the relative relationship of each tooth thickness of the spline of the second connecting member with respect to the spline of the first connecting member as shown in the following relationships (1), (2) and (3). It is in the joint structure of the joint.

(1) The tooth thickness of the spline in the arc portion extending a predetermined length from the base point of the first coupling member to both sides in the circumferential direction is set to a large tooth thickness, and the arc portion extending a predetermined length from the spline portion having the same tooth thickness. The tooth thickness of the spline is formed to have a medium tooth thickness, and the tooth thickness of the spline at an arc portion extending a predetermined length from the spline portion having the same tooth thickness is formed to have a small tooth thickness.

(2) The first before spline connection
And the tooth flank gaps of the spline meshing portion of the second coupling member are present in the spline portion having a small tooth thickness and the spline portion having a medium tooth thickness and are substantially zero in the spline portion having a large tooth thickness, and the small tooth The thickness of the thick spline portion is larger than that of the middle tooth thickness spline portion.

(3) The tooth surface gaps before and after the tooth thickness of each spline in the spline portion having the small tooth thickness and the spline portion having the medium tooth thickness are substantially the same.

[0011]

In the connecting structure of the spline connecting portion configured as described above, the engagement state of the splines before the second connecting member is fastened to the first connecting member is large as shown in FIG. The tooth surface gap is zero in the tooth thickness spline portion, the tooth surface gap is small in the medium tooth thickness spline portion, and the tooth surface gap is large in the small tooth thickness spline portion. Further, since the tooth flank gaps δ1 and δ2 of each spline in the spline portion of medium tooth thickness and in the spline portion of small tooth thickness are substantially the same, in the state where the second coupling member is fastened to the first coupling member. Since the above tooth flank gap δ2 is approximately half of the conventional tooth flank gap δ2, the amount of deformation during tightening of the second coupling member is about half that of the conventional coupling structure shown in FIGS. 4 and 5. Becomes

Therefore, in the state where the second coupling member is fastened to the first coupling member for the above reasons, it is possible to perform fastening at least at three points of the large tooth thickness spline portion and both small tooth thickness spline portions. As a result, a stronger tightening effect can be obtained, and rattling can be eliminated to greatly suppress the occurrence of wear and abnormal noise during use.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. In FIGS. 1 and 2, there is shown a steering shaft 10 shown in FIG. 3 which is a first connecting member constituting a connecting structure according to the present invention. The intermediate shaft 11 and the yoke 21 of the universal joint 20 which is the second coupling member are shown. The universal joint 20 connects the main shaft 12 to the intermediate shaft 11, and the yoke 21 connects the other yoke 2 to the main shaft 12.
It is rotatably connected to 2. The intermediate shaft 11 is connected to a gear box (not shown) via a second universal joint 30.

The intermediate shaft 11 has an outer spline portion on the outer periphery of the shaft portion 11a, and the yoke 21 has a tubular shape with a C-shaped cross section.
A pair of flanges 21b, 21 for tightening at one end of the
In addition to being provided with c, an inner spline portion is provided on the inner circumference of the tubular portion 21a. The yoke 21 is fitted on the outer circumference of the intermediate shaft 11 and is provided on both flange portions 21b,
The intermediate shaft 11 is fastened to the intermediate shaft 11 by bolts 23a and 23b inserted through 21c so that the splines mesh with each other and are spline-coupled.

The spline 11b of the intermediate shaft 11 is formed to have the same tooth thickness, while the spline of the yoke 21 has a large tooth thickness, a medium tooth thickness and a small tooth thickness. It is formed in groups of three different tooth thicknesses. FIG. 1 shows a state before tightening in a fitted state of the intermediate shaft 11 and the yoke 21. In this state before tightening, the yoke 21 has a portion facing the center between the flange portions 21b and 21c. It is the base point C where the diameter is reduced.

In the spline portion of the yoke 21, both sides thereof are formed symmetrically with respect to the base point C as a center. That is, the splines on both sides of the base point C of the yoke 21 are large tooth thickness splines (large tooth thickness splines 21d), and the splines on both sides of the same spline 21d are medium tooth thickness splines (medium tooth thickness splines 21e). The splines on both sides of the spline 21e are each formed as a spline having a small tooth thickness (small tooth thickness spline 21f).

Each of these splines 21d, 21e, 2
The relationship of the tooth thickness of 1f is set as follows. That is, (1) The small tooth thickness spline 21f and the middle tooth thickness spline 21e are set so that the tooth flank gaps between the spline meshing portions of the intermediate shaft 11 and the yoke 21 before tightening are small.
In addition to the presence of the large tooth thickness spline 21d
Is approximately zero and is larger than the middle tooth thickness spline 21e in the small tooth thickness spline 21f. (2) The tooth surface gap before and after the tooth thickness of each 1 spline in the small tooth thickness spline 21f and the middle tooth thickness spline 21e. Are set to be almost the same.

In the connecting structure of the spline connecting portion constructed as described above, the engagement state of the splines before the yoke 21 is fastened to the intermediate shaft 11 is as shown in FIG. The surface clearance is zero, the tooth surface clearance is small in the middle tooth thickness spline 21e, and the tooth surface clearance is large in the small tooth thickness spline 21f. Further, since the tooth flank intervals δ1 and δ2 of the splines 21e and 21f in the middle tooth thickness spline 21e and the small tooth thickness spline 21f are substantially the same, the yoke 2
1 is fastened to the intermediate shaft 11, the tooth gap δ2 is approximately half of the conventional tooth gap δ2. Therefore, the deformation amount of the yoke 21 at the time of tightening is shown in FIGS. 4 and 5. It is about half compared to the combined structure of.

Therefore, for this reason, when the yoke 21 is fastened to the intermediate shaft 11, at least the large tooth thickness spline 2 is provided as shown in FIG.
1d and both small tooth thickness splines 21f can be tightened at three positions to obtain a stronger tightening effect, and play is eliminated to cause wear during use.
The generation of abnormal noise can be greatly suppressed.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a bolt tightening portion of FIG. 3 showing a fitted state of two joining members that constitute a spline joining structure according to an embodiment of the present invention.

FIG. 2 is a sectional view corresponding to FIG. 1, showing the same coupling structure.

FIG. 3 is a side view showing a schematic configuration of a steering shaft adopting the same coupling structure.

FIG. 4 is a sectional view showing a conventional spline coupling structure corresponding to FIG. 1.

FIG. 5 is a sectional view corresponding to FIG. 2, showing the spline coupling structure.

[Explanation of symbols]

10 ... Steering shaft, 11 ... Intermediate shaft (first coupling member), 11b ... Spline,
20 ... Universal joint, 21 ... Yoke (second coupling member), 2
1d ... Large tooth thickness spline, 21e ... Medium tooth thickness spline,
21f ... Small tooth thickness spline.

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁵ Identification code Office reference number FI technical display location // B62D 1/16 9142-3D

Claims (1)

[Claims] 1. A shaft-shaped first coupling member having an outer spline on an outer peripheral side, a cylindrical shape having an inner spline on an inner peripheral side, and being capable of being reduced in diameter with respect to one point in the circumferential direction as a base point. And a second coupling member externally fitted on the coupling member, wherein the second coupling member is reduced in diameter and fastened onto the first coupling member by spline coupling. The relative relationship of each tooth thickness of the spline of the second connecting member to the spline of the first connecting member is set to the relationship shown in the following (1), (2) and (3). Joint structure of spline joint. (1) The tooth thickness of the spline in the arc portion extending a predetermined length from the base point of the first coupling member to both sides in the circumferential direction is set to a large tooth thickness, and the spline in the arc portion extending a predetermined length from the spline portion having the same tooth thickness is used. The tooth thickness is formed to be a medium tooth thickness, and the tooth thickness of the spline in an arc portion extending a predetermined length from the spline portion having the same tooth thickness is formed to be a small tooth thickness. (2) The tooth flank gaps of the meshing portions of the splines of the first and second coupling members before the spline coupling are made to exist in the spline portion of the small tooth thickness and the spline portion of the medium tooth thickness, and the The spline portion should be substantially zero, and the spline portion with a small tooth thickness should be larger than the spline portion with a medium tooth thickness. (3) The tooth surface gaps before and after the tooth thickness of each spline in the spline portion having the small tooth thickness and the spline portion having the medium tooth thickness are substantially the same.