JPS63293324A - Bearing unit for universal joint - Google Patents

Abstract

PURPOSE:To make it possible to prevent a load concentration to one point by making a clearance between a trunnion and a roller the larger as the closer to the tip of the trunnion, and making the contact of the trunnion uniform by the inclination of the axis of the trunnion. CONSTITUTION:The clearance between the peripheral surface of a trunnion 31 and the peripheral surface of a roller 43 is set the larger as the closer to the tip of the trunnion 31 by the difference between the crownings 80 and 90. As a result, an inclination of the trunnion 31 and the bearing case responding to the minimum clearance cannot be avoided. However, when the trunnion 31 is inclined, the whole peripheral surface of the roller 43 and the peripheral surface of the trunnion 31 are contacted completely. The concentration of load to the tip side of the trunnion 31 can be prevented consequently.

Description

DETAILED DESCRIPTION OF THE INVENTION <Field of Industrial Application> The present invention relates to a bearing device mounted on a trunnion of a cross shaft in a universal joint.

<Prior art> An example of a conventional bearing device of this type is shown in Figures 10 to 13.
This will be explained with reference to the diagram. In addition, in FIG. 12 and FIG. 13, the slope of the trunnion is extremely thick (shown) for convenience of explanation.

In the figure, numeral 10 is a first yoke formed at the shaft end of the first rotating shaft 11, numeral 20 is a second yoke connected to the axial end of a second rotating shaft (not shown), numeral 30 is a cross shaft, The reference numeral 40 indicates a bearing device, the reference numeral 50 a sealing device, and the reference numeral 60 a grease outlet serving as a grease supply port to the bearing device 40.

A bearing device 40 is attached to each trunnion 31 of the cross shaft 30, and the bearing case 41 of this bearing device 40 is engaged with the first yoke 10 and the second yoke 20 and connected with bolts 70 or the like. ing.

The bearing device 40 includes a bearing case 41. Thrust Wano,/ya42. It is composed of a plurality of rollers 43, and the rollers 43 are arranged in one row along the axial direction of the trunnion 31, for example.

Between the outer circumferential surface of the rollers 43 and the outer circumferential surface of the trunnion 31 of the cross shaft 30, there is a minute gap on the order of μm, which is necessary as the bearing internal gap. This gap is substantially uniform from the distal end side to the proximal end side of the trunnion 31.

The sealing device 50 includes an oil seal 51. It consists of a slinger 52° water seal 53, and a trunnion 3.
It is attached to the proximal end side of 1.

By the way, in the bearing device 40, so-called 80° and 90° roundings are generally formed at the corners of both ends of the rollers 43 in the axial direction, respectively, in order to prevent loads from being concentrated there. These roundings 80, 90 are symmetrically distributed on the rollers 43.

<Problems to be Solved by the Invention> However, the conventional example having such a configuration has the following problems.

For example, when transmitting power from the first yoke 10 (or second yoke 20) to the second yoke 20 (or first yoke 10), the two trunnions 31 of the cross shaft 30 are transmitted from the first yoke 10 via the bearing case 41. A force is applied to the second trunnion from the other two trunnions 31 through the bearing case 41.
Since the force acts on the yoke 20, a radial load acts on the rollers 43 interposed between the bearing case 41 and the trunnion 31.

The contact state between the roller 43 and the trunnion 31 at this time will be explained using FIG. 12.

As mentioned above, there is a minute gap in μm order between the outer circumferential surface of the rollers 43 and the outer circumferential surface of the trunnion 31 of the cross shaft 30, which is the internal gap necessary for functioning as a bearing. Initially, as shown in FIG. 12 ta+, when transmitting the information, the axial center of the trunnion 31 and the axial center of the bearing case 41 are not parallel to each other, and the gap bone tilts slightly, causing the distal end side of the trunnion 31 to tilt. The trunnion 31 is brought into contact only with the tip end side of the roller 43, and as shown in FIGS.
3, from the distal end side to the proximal end side almost entirely.

Because of this phenomenon, the trunnion 31 of the roller 43
There is a difference between the load acting on the distal end side and the load acting on the base end side of the trunnion 31 of the roller 43.

Specifically, the distribution of the load acting on the rollers 43 will be explained with reference to FIG. 13.

As shown in the figure, the load distribution acting on the distal end side of the trunnion 31 of the roller 43 is larger than the load distribution acting on the proximal end side of the trunnion 31 of the roller 43. It is known that the load applied to the end side of the trunnion 31S'i of the roller 43 is approximately three times larger than the load applied to the proximal end of the trunnion 31S'i of the roller 43, although it varies slightly depending on the conditions. 31 Load is concentrated on the tip side.

For this reason, the tip of the trunnion 31 of the roller 43 is separated by 'fi1 (flaking phenomenon) at a relatively early stage.
This tends to occur, resulting in a shortened bearing life.

The present invention was devised in view of these circumstances, and aims to extend the life of the bearing by preventing peeling of the rollers at an early stage.

<Means for Solving the Problems> In order to achieve the above object, the present invention has the following configuration.

That is, the bearing device for a universal joint according to the present invention is mounted on a trunnion of a cross shaft in a universal joint, and includes a plurality of rollers arranged in one or more rows along the axial direction of the trunnion. By setting the amount of crowning on the distal end side of the trunnion applied to the roller to be larger than the amount of crowning on the proximal end side of the trunnion, the outer circumferential surface of the trunnion, the inner circumferential surface of the bearing case, and the The trunnion is characterized in that the gap between it and the outer circumferential surface of the roller is made larger on the tip side of the trunnion.

Effect〉 The effects of the configuration of the present invention are as follows.

The gap between the outer circumferential surface of the trunnion, the inner circumferential surface of the bearing case, and the outer circumferential surface is larger at the tip of the trunnion, so when transmitting power, the axis of the trunnion and the axis of the bearing case should be aligned with the smallest gap bone. It is unavoidable that the rollers will tilt slightly, but when this tilts, almost the entire outer circumferential surface of the trunnion comes into contact with almost the entire outer circumferential surface of the trunnion, which reduces the load on the rollers. I can no longer concentrate on one point.

Therefore, the difference between the load acting on the distal end side of the trunnion of the roller and the load acting on the proximal end side of the trunnion becomes smaller than in the past.

<Example> Hereinafter, an example of the present invention will be described in detail based on the drawings.

A first embodiment of the present invention is shown in FIGS. 1 to 3. In these figures, FIGS. 10 to 13 of the conventional example
The same reference numerals as those attached to the figures refer to the same parts or corresponding parts. In addition, in FIGS. 1 to 3 according to this embodiment, for convenience of explanation, the inclination of the trunnion and the difference in diameter between both ends of the roller in the axial direction are shown to be extremely large.

In this embodiment, descriptions of structures similar to those of the conventional example will be omitted, and different structures will be described in detail.

In this embodiment, a bearing device using a single roller 43 is taken as an example, and crowning 80 is distributed at both ends of the roller 43 in the axial direction.
90 is made asymmetrical.

That is, by making the amount of crowning 80 distributed on the tip side of the trunnion 31 of the roller 43 larger than the amount of crowning 90 distributed on the base end side of the trunnion 31 of the roller 43, the outer periphery of the roller 43 on the tip side of the trunnion 31 is made larger. The gap between the surface and the outer circumferential surface of the distal end of the trunnion 31 and the inner circumferential surface of the bearing case 41 is set to It is made larger in micrometers than the gap between it and the inner circumferential surface.

The amount of crowning 80.90 is changed by changing the widths A and B in the axial direction and the angle of inclination θ. A possible method is to keep A and B constant and change the inclination angle θ. In this embodiment, the former is used.

In other words, by keeping the inclination angle θ of the crownings 80 and 90 constant and making the width A of the crowning 80 larger than the width B of the crowning 90, the amount of the crowning 80 on the tip side of the trunnion 31 on the roller 43 can be reduced. It is thicker than the crowning 90 on the proximal end side of the trunnion 31.

Next, the operation during power transmission will be explained using FIG. 2.

The gap between the outer circumferential surface of the trunnion 31 and the inner circumferential surface of the bearing case 41 and the outer circumferential surface of the roller 43 is
Because of the crowning difference of 80.90, the distal end side of the trunnion 31 of the roller 43 is set much larger, so it is inevitable that the trunnion 31 and the bearing case 41 will have a gap of 1 with respect to the minimum gap bone.

However, since there is a crowning 80 on the outer circumferential surface of the roller 43 on the distal end side of the trunnion 31, when the trunnion 31 is tilted as described above, as shown in FIG. The range of contact with the outer circumferential surface of the tip end of the trunnion 31 becomes wider than before, and as shown in FIGS. , the entire outer peripheral surface of the roller 43 and the trunnion 31
The outer circumferential surface of the outer circumferential surface of the outer circumferential surface of

As shown in FIG. 3, the distribution of the load acting on the roller 43 at this time is as shown in FIG.
The difference between the two sides is much smaller than before. That is, by changing the amounts of the crownings 80 and 90, it is possible to prevent the load from concentrating on the tip end side of the trunnion 31 of the roller 43 as in the conventional case.

According to this embodiment, in which the amounts of the crownings 80 and 90 formed at both ends of the roller 43 in the axial direction are varied, the distribution of the load acting on the roller 43 can be made almost equal.

Hereinafter, a bearing device of a type in which rollers 43 are arranged in two rows will be described in second to fourth embodiments.

In the drawings of any embodiment, the same reference numerals as those in FIGS. 1 to 3 of the first embodiment refer to the same parts or corresponding parts, and the same configurations are used for each embodiment. Only the different configurations will be explained in detail, omitting the explanation of the above.

A second embodiment of the present invention is shown in FIGS. 4 and 5.

In this embodiment, both the crownings 80a, 90a of the first row of rollers 43a from the tip side of the trunnion 31 and the both crownings 80b, 90b of the second row of rollers 43b are distributed asymmetrically, and the amount thereof is The settings are the same for each column.

In other words, the crowning 80a distributed to the tip side of the trunnion 31 in the first row of rollers 43a and the second row of rollers 4
3b, the amount of crowning 80b distributed to the trunnion tip side is the same as that of the crowning 80b, and the first row of rollers 43a has the same amount of crowning 9 distributed to the base end side of the trunnion 31.
0a and the amount of the crowning 90b distributed to the base end side of the trunnion 31 in the second row of rollers 43b are set to be the same, and the crowning Boa,
The amount of BobO is made larger than the amount of the crownings 90a and 90b.

As a result, the gap between the outer circumferential surface on the tip side of the trunnion 31, the inner circumferential surface of the bearing case 41, and the outer circumferential surface on the tip side of the trunnion 31 of the first row of rollers 43a is reduced.
The gap is larger than the gap between the outer circumferential surface of the proximal end of the bearing case 41 and the inner circumferential surface of the bearing case 41, and the outer circumferential surface of the proximal end of the trunnion 31 of the second row of rollers 43b.

The amounts of each of these crownings are set by keeping the inclination angle θ constant and changing the width in the axial direction.

That is, the width of each of these crownings is AI > B+, Ax > B! , At=Az,
B+ = B.

It is.

With this configuration, the distribution of the load acting on the rollers 43a and 43b is similar to that of the first embodiment, as shown in FIG.
It is possible to prevent the load from concentrating on the roller 43a disposed on the distal end side, and the difference between the load acting on the roller 43b disposed on the proximal end side compared to the conventional one. It can be made much smaller.

Measure 1: A third embodiment of the present invention is shown in FIGS. 6 and 7.

Each crowning 80a, 90a of the first row of rollers 43a and each crowning 80b of the second row of rollers 43b.

90b are all distributed symmetrically, and the amount is changed from column to column.

In other words, each crowning 80a1 of the first row of rollers 43a
90a are set to be the same, and the amounts of each of the crownings 80b and 90b of the second row of rollers 43b are also set to be the same, so that each crowning 3Qa of the first row of rollers 43a is set to the same amount.
, 90a are set larger than the respective crownings 80b, 90b of the second row of rollers 43b.

The width of each of these crownings is AI = Bl, At = B! , AH>Bz.

With such a configuration, the outer peripheral surface of the tip side of the trunnion 31, the inner peripheral surface of the bearing case 41, and the first row of rollers 43a
The gap between the outer circumferential surface of the distal end of the trunnion 31, the outer circumferential surface of the proximal end of the trunnion 31, the inner circumferential surface of the bearing case 41, and the outer circumferential surface of the proximal end of the trunnion 31 of the second row of rollers 43b. It is set larger than the gap between the two.

In this embodiment as well, the distribution of the load acting on each roller 43a, 43b is almost the same as in the second embodiment, as shown in FIG.

A fourth embodiment of the present invention is shown in FIGS. 8 and 9.

Each crowning 8Qa, 90a of the first row of rollers 43a and each crowning 80b of the second row of rollers 43b.

90b are all distributed asymmetrically, and the amount is changed from column to column.

In other words, for the rollers 43a in the first row, the amount of crowning 80a distributed to the tip side of the trunnion 31 is larger than the amount of crowning 90a distributed to the base end side of the trunnion 31, and for the rollers 43a in the second row, The amount of crowning 80b distributed to the distal end of the trunnion 31 is changed to the amount of crowning 90 distributed to the proximal end of the trunnion 31.
The amount of crowning 80a, 90a of roller 43a of the first row is set larger than the amount of crowning 80b, 9Qb of roller 43b of second row.

The width of each of these crownings is A+ >3. , At>Bt, A+>Ax,
B+ >B.

* Bl At It is.

In this embodiment as well, the load distribution acting on each roller 43a, 43b is substantially the same as in the second and third embodiments, as shown in FIG.

In the first to fourth embodiments described above, the amount of crowning was changed only by the width in the axial direction, but the present invention is not limited to this, and if the inclination angle is changed in addition to changing the width, further various changes can be made. Examples are possible.

In addition, in the second to fourth embodiments described above, two rows of rollers 43
Although the bearing device 40 having the bearing devices a and 43b is illustrated, the present invention is not limited thereto, and includes, for example, a bearing device having three or more rows.

In all of the embodiments described above, conventional problems are solved by changing the amount of crowning of the rollers. It is also possible to solve the above problem by increasing the inner diameter from the opening side to the bottom side.

<Effect of the invention> According to the present invention, the following effects are achieved.

Since the gap between the trunnion and the bearing case is larger at the tip of the trunnion, it is unavoidable that the axis of the trunnion and the axis of the bearing case are slightly inclined with respect to the smallest gap bone, but this inclination causes , substantially the entire outer circumferential surface of the trunnion comes into even contact with substantially the entire outer circumferential surface of the trunnion, thereby preventing the load from concentrating on one point on the roller.

In this way, since the concentration of load on the rollers can be eliminated, the difference between the load acting on the rollers disposed on the distal end side and the load acting on the rollers disposed on the proximal end side can be reduced compared to the conventional method. It can be made much smaller.

In other words, since the distribution of the load acting on the rollers can be made almost uniform, peeling of the rollers can be prevented from occurring at a relatively early stage, contributing to extending the life of the bearing.

[Brief explanation of drawings]

1 to 3 relate to the first embodiment of the present invention, and FIG. 1 is a longitudinal cross-sectional side view showing the main parts of the bearing device installed on the cross shaft, and FIG. FIG. 3 is an explanatory diagram showing the load distribution in the state of FIG. 2 (C1). FIGS. 4 to 9 show the second to fourth embodiments of the present invention. 4, FIG. 6, and FIG. 8 are diagrams corresponding to FIG. 1, and FIG. 5, FIG. 7, and FIG. 9 are diagrams corresponding to FIG. 3. Figures 10 to 13 relate to the conventional example;
Figure 0 is an exploded perspective view showing the universal joint.
Figure 1 is a vertical sectional side view of the main part showing the cross shaft and bearing device, Figure 12 (al or C1 is a partial sectional view of the bearing device for explaining the operation, and Figure 13 is a partial sectional view of the bearing device in the state of Figure 12 (C1). It is an explanatory diagram showing load distribution. 30... Cross shaft 31... Trunnion 40... Bearing device 41... Bearing case 43... Rollers 80, 90... Crowning.

Claims (1)

[Claims] (1) In a bearing device equipped with a plurality of rollers mounted on a trunnion of a cross shaft in a universal joint and arranged in one or more rows along the axial direction of the trunnion, By setting the amount of crowning on the tip side of the trunnion to be larger than the amount of crowning on the base end side of the trunnion, the gap between the outer circumferential surface of the trunnion, the inner circumferential surface of the bearing case, and the outer circumferential surface of the roller can be reduced. A universal joint bearing device characterized by being larger toward the tip.