JPH11190356A - Roller bearing for cross-joint - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make the contact surface pressure uniform by providing such an arrangement that the height of a contact surface of an annular contact part formed in the inner surface of the bottom part of a shell type outer race is gradually reduced from the inner diameter side to the outer diameter side, and by making the contact surface into entire surface contact with a shaft end face of a spider shaft in a pre-pressed condition. SOLUTION: A convex zone A serving as a contact surface of a contact apt 1b1 is a tapered surface having a tapered angle δ in such a direction that the height (h) thereof, measured from the inner surface of the bottom part, is reduced from the inner diameter side to the outer diameter side. When a shaft end face 12a1 of a spider shaft 12a is made into contact with the contact part 1b1 by a predetermined degree of pre-pressure, the contact part 1b1 is elastically displaced by a pre-load exerted from the shaft end face 12a1 (since the bottom part is elastically deformed by the pre-load), and accordingly, the convex zone A is made into entire surface contact with the shaft end face 12.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a roller bearing interposed between a shaft of a spider and a yoke in a cross joint for connecting a propeller shaft of an automobile or the like.

[0002]

2. Description of the Related Art For example, in a vehicle driven by a front engine and rear wheels, an engine, a clutch, and a transmission are normally concentrated forward, and a reduction gear unit and a drive axle are concentrated rearward. A propeller shaft is used. The propeller shaft is connected to the transmission and the reduction gear device at an angle θ in terms of body shaping, and a cross joint (also called a universal joint, a hook joint, or a cardan joint) is often used for this connection. ing.

Generally, as shown in FIG. 6, a cross joint includes a pair of yokes 11 on an input shaft side and an output shaft side.
One spider 12 (also referred to as a cross shaft or a cross) having four cross-shaped spider shafts 12a, and four needle roller bearings 13;
The two spider shafts 12a are connected to the yoke 11 via needle roller bearings 13, respectively. The needle roller bearing 13 includes a cup-shaped outer ring 13a having a cylindrical portion 13a1 and a bottom portion 13a2, and a plurality of needle rollers 13b incorporated into the inner peripheral surface of the cylindrical portion 13a1 of the outer ring 13a.
3b contacts the outer peripheral surface of the spider shaft 12a,
The inner surface of the bottom portion 13a2 is the shaft end surface 12 of the spider shaft 12a.
a1.

When the cross joint rotates at an operating angle θ, a relative swinging motion occurs between the spider shaft 12a and the outer ring 13a. The swing angle is twice (2θ) the operating angle θ. . ), Since sliding friction occurs at the contact portion between the shaft end surface 12a1 and the inner surface of the bottom portion 13a2, the contact portion is usually lubricated with grease to reduce this.

[0005]

The outer ring of this type of needle roller bearing is formed by forming a metal plate material such as a steel plate into a cup shape (press processing or the like) by a shell type, and by forging and cutting a steel material or the like. There are two types of solid type, but in the case of shell type outer ring, the annular contact part provided on the inner surface of the bottom is pressed against the shaft end face of the spider shaft in a preload state, and the elastic displacement of the contact part due to the preload Thereby, the contact portion comes into contact with the shaft end surface of the spider shaft in the outer diameter side region. Therefore, there is a problem in that the contact surface pressure in the outer diameter side region of the contact portion is increased, and wear is promoted.

An object of the present invention is to reduce the contact surface pressure between the shaft end surface of the spider shaft and the contact portion of the outer ring, and to reduce wear of the contact portion.

[0007]

In order to solve the above-mentioned problems, according to the present invention, the height of the contact surface of an annular contact portion provided on the inner surface of the bottom of the shell type outer ring is increased from the inner diameter side to the outer diameter side. The contact surface was brought into contact with the shaft end surface of the spider shaft in a preloaded state. When the shaft end surface of the spider shaft is brought into contact with the contact portion with a predetermined preload amount, the contact portion is elastically displaced by the preload applied from the shaft end surface (because the bottom portion is elastically deformed by the preload load), and the contact surface of the contact portion is spidered. Contact the entire shaft end face.

[0008]

Embodiments of the present invention will be described below.

FIG. 1 shows a needle roller bearing for a cross joint according to this embodiment. The needle roller bearing includes a cup-shaped outer ring 1 having a cylindrical portion 1a, a bottom portion 1b, and a flange portion 1c, and a plurality of needle rollers 2 arranged on the inner peripheral surface of the cylindrical portion 1a. A shaft (spider shaft) 12a of the spider 12 shown in FIG. 6 is fitted into the inner diameter of the needle roller 2. Note that a seal may be attached to the opening (flange 1c) side of the outer race 1.

In this embodiment, the outer race 1 is a shell type press-formed from a steel plate material, and a raceway surface 1a1 with which a needle roller 2 contacts is formed on the inner peripheral surface of a cylindrical portion 1a, and an inner surface of a bottom portion 1b. An annular contact portion 1b1 with which the shaft end surface 12a1 of the spider shaft 12a comes into contact is formed at the center portion of the spider shaft 12a. Grease reservoirs 1b2 and 1b3 are formed on the inner and outer diameter sides of the contact portion 1b1, respectively.

As shown in FIG. 2, the contact portion 1b1 of the bottom 1b has a large number of convex regions A (region A1, region A1).
2, a region A3) and a concave region B (region B1, region B2) are formed. The convex region A is a substantially Y-shaped region, and its cross section has a substantially trapezoidal shape (FIG. 2B).
reference). Region A1 and region A forming the Y-head of convex region A
2 each reach the outer diameter of the contact portion 1b1, and the region A3 forming the Y-shaped leg reaches the inner diameter of the contact portion 1b1. Concave area B
Is a region surrounded by the convex regions A, a region B1 surrounded by two circumferentially adjacent convex regions A, and a region B2 surrounded by the regions A1 and A2 of the convex regions A. Consists of The region B1 has a substantially rhombic shape, communicates with both the inner and outer diameters of the contact portion 1b1, and has a width that decreases from the inner diameter to the outer diameter. The region B2 has a substantially fan shape and communicates with the outer diameter of the contact portion 1b1. In the contact portion 1b1 having such a pattern, the convex region A comes into contact with the shaft end surface 12a1 of the spider shaft 12a, and the concave region B serves to hold and distribute grease.

The pattern of the protruding region A serving as the contact surface is shown in FIG.
Are set based on the reference shown in an enlarged manner. First, the bottom 1b
A number of reference lines R1 are set at a pitch angle α1 in the radial direction from the center O of the inner surface. Next, with respect to each reference line R1, one of the circumferential directions (for example, counterclockwise in FIG.
A reference line R2 having a reference angle R2 and a reference line R3 having an inclination angle α2 in the other circumferential direction (for example, clockwise in the figure) are set. Then, the region A1 has a constant width along the reference line R2.
Is provided, a region A2 is provided at a constant width along the reference line R3,
In addition, the region A1 and the region A2 are merged in the region on the inner diameter side of the contact portion 1b1 (the reference line R2 and the reference line R3 intersect at the point O1) to provide the region A3 along the reference line R1. In this manner, a large number of substantially Y-shaped convex regions A reaching the inner and outer diameters of the contact portion 1b1 are formed at the pitch angle α1. In this embodiment, the pitch angle α1 is 12
° and the inclination angle α2 are set to 3 °. Therefore,
The total number of the convex regions A is 30, and the total number of the regions A1 and A2 is 60. Further, the region B1 and the region B2 of the concave region B
Are 30 in each case.

Further, as shown in FIG.
The convex region A serving as the contact surface of b1 is a tapered surface having a taper angle δ in a direction in which the height h from the inner surface of the bottom 1b decreases from the inner diameter side to the outer diameter side. As shown in FIG. 4B, when the shaft end surface 12a1 of the spider shaft 12a is brought into contact with the contact portion 1b1 with a predetermined preload amount P, the shaft end surface 12a1
The contact portion 1b1 is elastically displaced by the preload load P received from the shaft (because the bottom portion 1b is elastically deformed by the preload load P), and the convex region A comes into full contact with the shaft end surface 12a1. Therefore, the contact surface pressure at the contact portion 1b1 is made uniform, and the wear of the contact portion is reduced.

The taper angle δ of the convex area A serving as the contact surface is determined by the conditions of use, the preload P, the material of the outer ring 1, the thickness, the inner diameter,
Considering the inner and outer diameter dimensions of the contact portion 1b1, it is set to a value within a range that can achieve the above-described effect. Specifically, the taper angle δ is such that even when the convex region A and the shaft end surface 12a1 come into full contact with each other in a state where a predetermined preload P is applied and a tilt load is generated during rotation of the joint, the contact surface pressure becomes smaller. It is desirable that the value be set so that the balance is maintained and the convex region A and the shaft end surface 12a1 do not cause uneven contact in the outer diameter side region, for example, a value within the range of δ ≦ 1 °.
Note that the convex region A serving as a contact surface is not limited to a tapered surface, and may be a surface having a slight curvature (an arc surface or the like) as long as the above-described effects can be achieved.

In the embodiment shown in FIG. 5, the pattern of the contact portion 1b1 is opposite to that of the above embodiment. That is, the substantially Y-shaped convex region A (A1, A2,
A3) is a concave region A ′ (A′1, A′2, A′3), and the concave region B (B1, B2) of the above embodiment is a convex region B ′ (B ′).
1, B'2). The concave region A 'is a substantially Y-shaped region, and its cross section has a substantially inverted trapezoidal shape. Regions A'1 and A'2 forming the Y-shaped head of the concave region A 'communicate with the outer diameter of the contact portion 1b1, and the region A'3 forming the Y-shaped leg communicates with the inner diameter of the contact portion 1b1. The convex region B ′ is a region partitioned by the concave region A ′, and includes a region B′1 divided into two circumferentially adjacent concave regions A ′, and a region A′1 of the concave region A ′. An area A'2 and an area B'2 partitioned into areas. The region B'1 has a substantially rhombus shape, and the region B'2 has a substantially fan shape. In the contact portion 1b1 having such a pattern, the convex region B 'is formed by the spider shaft 12a.
And the concave region A ′ serves to hold and distribute grease. The convex region B ′ serving as the contact surface is
The taper angle δ shown in FIG.
The pattern of the concave area A ′ is set based on the reference shown in FIG. 3 according to the convex area A of the above embodiment. The convex region B ′ serving as the contact surface may have a curvature (an arc surface or the like).

The pattern of the contact portion is not limited to the above-described substantially Y-shape, but may be any shape such as a radial shape or a dimple shape.

[0017]

As described above, according to the present invention,
The height of the contact surface of the annular contact portion provided on the bottom inner surface of the shell type outer ring is gradually reduced from the inner diameter side to the outer diameter side, and the contact surface is entirely preloaded on the shaft end surface of the spider shaft. Since the contact is made, the contact surface pressure is made uniform, the wear of the contact portion is reduced, and the durability life is improved.

[Brief description of the drawings]

FIG. 1 is a sectional view (FIG. A) showing a needle roller bearing according to the present invention, and an enlarged sectional view (FIG. B) of an outer ring in FIG.

FIG. 2 is a plan view (FIG. A) and a partially enlarged cross-sectional view (FIG. B) showing a contact portion of a bottom inner surface of an outer ring.

FIG. 3 is a partially enlarged plan view of a contact portion.

FIG. 4 is a cross-sectional view (FIG. A) of the contact portion along the radial direction, showing a contact state when the shaft end face of the spider shaft is brought into contact with the contact portion in a preloaded state (FIG. B).

FIG. 5 is a plan view (FIG. A) and a partially enlarged sectional view (FIG. B) showing a contact portion on the inner surface of the bottom of the outer race according to another embodiment of the present invention.
It is.

FIG. 6 is an exploded perspective view showing a general configuration of a cross joint.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Outer ring 1a Cylindrical part 1b Bottom part 1b1 Contact part 2 Needle roller

Claims (5)

[Claims] 1. A shell-type outer ring formed from a metal plate material into a cup shape having a cylindrical portion and a bottom portion, and having an annular contact portion on the inner surface of the bottom portion which comes into contact with a shaft end surface of a spider shaft of a cross joint in a preloaded state. In a cross-joint roller bearing having a plurality of rollers incorporated in the inner peripheral surface of a cylindrical portion of an outer ring, the height of the contact surface of the contact portion gradually decreases from the inner diameter side to the outer diameter side. A roller bearing for a cross joint, characterized in that: 2. The cross-joint roller bearing according to claim 1, wherein the contact surface comes into full contact with the shaft end surface of the spider shaft due to elastic displacement of the contact portion when a predetermined preload is applied. 3. An annular contact portion which is formed from a metal plate material into a cup shape having a cylindrical portion and a bottom portion, and has an annular contact portion on the inner surface of the bottom portion which comes into contact with a shaft end surface of a spider shaft of a cross joint in a preloaded state. In an outer ring of a shell-type cross joint roller bearing having a roller raceway surface on an inner peripheral surface, a height of a contact surface of the contact portion gradually decreases from an inner diameter side to an outer diameter side. Outer ring of roller bearing for cross joint. 4. The outer race of a roller bearing for a cross joint according to claim 3, wherein the contact surface makes full contact with the shaft end surface of the spider shaft due to elastic displacement of the contact portion when a predetermined preload is applied. 5. A metal plate material is formed into a cup shape having a cylindrical portion and a bottom portion, and has an annular contact portion on the inner surface of the bottom portion, and the height of the contact surface of the contact portion increases from the inner diameter side to the outer diameter side. A roller bearing having a shell-shaped outer ring that gradually decreases toward the outer ring, a plurality of rollers built into the inner peripheral surface of the cylindrical portion of the outer ring, and a spider shaft of a cross joint. A cross joint in which the shaft is inserted and the contact surface of the contact portion is brought into contact with the shaft end surface of the spider shaft with a predetermined amount of preload, and the contact surface and the shaft end surface are entirely contacted by the elastic displacement of the contact portion. Roller bearing device.