JP4370982B2 - Thrust washer and cross shaft joint using the same - Google Patents

Description

  The present invention relates to a thrust washer for a cross joint used for connecting a drive shaft and the like, and a cross joint using the same.

  A conventional cross shaft joint is used for a power transmission shaft or the like that couples a pair of rotating shafts to each other so as to adapt the change in angle formed by them. Such a cross shaft joint includes a cross shaft having four shaft portions arranged in a cross shape, and a bearing that is rotatably attached to the tip of each shaft portion of the cross shaft via a plurality of needle rollers or the like. A cup, and a thrust washer disposed between the bearing cup and the shaft end face. Oil thrust grooves extending from the central through hole toward the outer edge are provided on both end faces of the thrust washer so that the lubricating oil flows to each sliding portion in the bearing cup and lubricates the inside. (For example, refer patent document 1).

JP 2001-234842 A (page 3)

From the viewpoint of labor saving and the like in recent years, there is an increasing need for downsizing of cross joints used for rotating shafts and the like. Among them, as a measure for reducing the size of the cross joint, it is conceivable to reduce the thickness of the thrust washer.
However, the thrust washer is provided with an oil groove as described above, and if the plate thickness is excessively thin, cracks will occur starting from the end of the oil groove near the inner and outer peripheral edges of the thrust washer. In some cases, it was lowered and could not be used. For this reason, it is difficult to reduce the thickness of the thrust washer beyond a certain level, and the thickness of this thrust washer is one of the factors that hinders the miniaturization of the cross joint.

  The present invention has been made in view of such circumstances, and a thrust washer for a cross joint that can suppress the occurrence of cracks even if the plate thickness is reduced, and a cross joint that can be miniaturized by using the same. The purpose is to provide

In order to achieve the above object, the present invention has a disc shape with a through hole formed in the center thereof, and a plurality of groove portions extending from the inner peripheral edge on the through hole side toward the outer peripheral edge on both end faces thereof. In the thrust washer for a cross shaft joint formed with the outer peripheral edge and the inner peripheral edge when the groove formed on one end face and the groove formed on the other end face are viewed from the end face in plan view. substantially intersect at the center, the one with the inner peripheral side end portion of the groove formed on the side end face, and the said other side of said formed groove in the end face the inner peripheral side end portion, that between the When viewed in plan from the end surface, they are arranged alternately and at substantially equal pitches with respect to the circumferential direction of the inner periphery, and are formed on the outer periphery side end of the groove formed on the one end surface and on the other end surface. The outer peripheral edge side end portion of the groove portion thus formed When viewed in plan from the end face, it is characterized by being arranged alternately with respect to the circumferential direction of the outer peripheral edge without overlapping.

According to the thrust washer configured as described above, the intersecting portion where the groove portion formed on the one end surface and the groove portion formed on the other end surface intersect has a thickness as a thrust washer. It is partially thinned, and the rigidity in that part can be reduced. Accordingly, when a stress is applied from the outside along with the use of the thrust washer, the stress in the vicinity of the center between the outer peripheral edge and the inner peripheral edge where the intersecting portion is located increases, so that the stress concentration is relatively high. It is possible to alleviate stress concentration on the inner and outer peripheral edges.

In particular , in the thrust washer, when the groove portion formed on the one side end surface and the groove portion formed on the other side end surface are viewed from the end surface, the gap between the outer peripheral edge and the inner peripheral edge is determined. It is crossing almost in the middle.
For this reason , the stress distribution in the radial direction of the thrust washer can be made more uniform by disposing the intersecting portion where the rigidity is decreased and the stress is increased at substantially the center between the outer peripheral edge and the inner peripheral edge. . Therefore, even when the thickness of the thrust washer is reduced, it is possible to prevent the stress from concentrating on a part and generating a crack.

In the thrust washer, the stress distribution in the radial direction can be made uniform. On the other hand, in order to make the stress distribution in the circumferential direction uniform, the inner peripheral edge of the groove formed on the one end face and the inner periphery of the groove formed on the other end face. and edge end portion, when viewed in plan from its end face, alternately and that are arranged at approximately equal pitches with respect to the circumferential direction of the inner peripheral edge.
For this reason , since the inner peripheral edge side edge part of the said groove part is arrange | positioned at equal pitch, it can prevent that the stress in the circumferential direction of the said thrust washer concentrates partially, and suppresses generation | occurrence | production of the crack by stress concentration more. Can do.

  The present invention also includes a cross shaft having four shaft portions arranged in a cross shape, a bottomed cylindrical bearing cup rotatably attached to the shaft portions, and a through hole formed in the center thereof. A plurality of groove portions extending from the inner peripheral edge on the through-hole side toward the outer peripheral edge are formed on both end faces, and are arranged between the bottom face of the bearing cup and the end face of the shaft part. The thrust washer is a thrust washer for a cross shaft joint as described above.

  Since the cross shaft joint configured as described above uses the above-described thrust washer for the cross shaft joint, the thickness of the thrust washer is made thinner while suppressing the occurrence of cracks. Can be used for shaft couplings.

  As described above, the thrust washer according to the present invention can make the distribution of stress in the radial direction more uniform, so that even if the plate thickness is reduced, the stress is concentrated on a part to suppress the generation of cracks. Can do. Further, the cross joint of the present invention can be downsized by using the thrust washer that can reduce the plate thickness.

Next, preferred embodiments of the present invention will be described with reference to the accompanying drawings. FIG. 1 is a partial cross-sectional view of a cross shaft joint using a thrust washer for a cross shaft joint according to an embodiment of the present invention. Such cross shaft joints are used for connecting power transmission shafts and steering shafts of automobiles, construction machines, railway vehicles, and the like.
In the figure, a cruciform joint 1 according to this embodiment includes a cruciform shaft 3 having four shaft portions 2 arranged in a cross shape, and a plurality of needle rollers 4 arranged around the shaft portions 2. The bottomed cylindrical bearing cup 5 that is rotatably mounted via the bearing 5 and the radial thrust force that is arranged between the bottom surface 5a of the bearing cup 5 and the end surface 2a of the shaft portion 2 is generated therebetween. A disc-shaped thrust washer 6 according to the present invention. In addition, since the structure of the bearing cup 5 etc. which are attached to the four shaft parts 2 of the cross shaft 3 is substantially the same, only one part is shown in FIG. 1, and the other part is omitted.

The shaft portion 2 and the bearing cup 5 constitute a rolling bearing by way of a plurality of needle rollers 4, and a pair of rotating shafts (not shown) and the like are respectively provided on the bearing cup 5 with yokes (not shown). The cross joint 1 is connected to each other so that changes in the angle formed by the pair of rotating shafts can be adapted to each other.
A ring-shaped seal member 7 is attached between the opening end portion 5b of the bearing cup 5 and the base end portion 2b of the shaft portion 2 so that the inside of the bearing cup 5 can be sealed. .
In addition, although the shaft part 2 and the bearing cup 5 comprised the rolling bearing by the some needle roller 4, you may comprise a rolling bearing using a cylindrical roller etc., for example.

  2A is a plan view of the thrust washer 6, and FIG. 2B is a side view of the thrust washer 6. As shown in FIG. This thrust washer 6 (hereinafter also referred to as a washer 6) is formed into a disk shape having a through hole 6a at the center using a hard resin or the like. A plurality of concave oil grooves 6f extending linearly from the inner peripheral edge 6d on the through-hole 6a side toward the outer peripheral edge 6e of the washer 6 are provided on both end faces 6b, 6c of the washer in the circumferential direction of the washer end faces 6b, 6c. Are formed at an equal pitch. The oil groove 6f constitutes a passage for supplying the lubricating oil supplied from the lubricant passage 2c (see FIG. 1) opened at the center of the shaft portion 2 to the needle rollers 4 and the like. Further, the groove depth of the oil groove 6 f is set to be smaller than ½ with respect to the thickness direction of the washer 6.

In addition, the arrangement of the plurality of oil grooves 6f when viewed from the washer end face is substantially the same on each of the washer both end faces 6b and 6c. On the other hand, the positional relationship between the oil groove 6f of the washer end surface 6b and the oil groove 6f of the washer end surface 6c is formed as follows. That is, in FIG. 2, the oil groove 6 f has the washer end surface 6 b, so that the pitches A and B between the oil groove end portion 6 f 1 on the washer end surface 6 b side and the oil groove end portion 6 f 1 on the washer end surface 6 c side are equal. 6c is formed. That is, the oil groove end portion 6f1 on the washer end surface 6b side and the oil groove end portion 6f1 on the washer end surface 6c side are alternately arranged at equal pitches in the circumferential direction of the inner peripheral edge 6d when viewed from the washer end surface 6b. Has been.
In this case, since the oil groove end 6f1 is arranged at equal intervals with respect to the circumferential direction of the inner peripheral edge 6d, it is possible to prevent the stress in the circumferential direction of the washer 6 from being partially concentrated.

  Further, when viewed in plan as described above, the oil groove 6f on the washer end surface 6b side and the oil groove 6f on the washer end surface 6c side have an intersection K that intersects with each other. The intersection K may be positioned between the inner peripheral edge 6d and the outer peripheral edge 6e. However, as shown in the present embodiment, the intersection K is set to be positioned approximately at the center between the inner peripheral edge 6d and the outer peripheral edge 6e. It is preferable. The reason is that the stress distribution in the radial direction of the washer 6 to be described later can be made more uniform as compared with the case where the intersecting portion K is not located at substantially the center between the inner peripheral edge 6d and the outer peripheral edge 6e. is there.

In the washer 6 according to the present embodiment configured as described above, since the oil groove 6f intersects at the intersecting portion K, the thickness of the washer 6 is partially reduced, and the rigidity in the portion is increased. Can be reduced. As a result, when stress is applied to the washer 6 by using the cross joint 1, stress near the center between the outer peripheral edge 6 e and the inner peripheral edge 6 d where the intersection K is located increases, so that stress concentration is relatively easy. The stress concentration on the inner peripheral edge 6d and the outer peripheral edge 6e can be alleviated, and the stress distribution in the radial direction of the washer 6 can be made more uniform. Therefore, even when the washer 6 is made thinner, it is possible to suppress the generation of cracks in the washer 6 due to stress concentration.
Moreover, since the plate | board thickness of the washer 6 can be made thin, the material required in order to shape | mold the washer 6 can be reduced, and the manufacturing cost can be reduced.

  Moreover, since the cross joint 1 of this embodiment can make the plate | board thickness of the washer 6 thin as mentioned above, the size reduction can be achieved.

  Next, the results obtained by analyzing and verifying the stress distribution acting on the washer 6 in the cross joint 1 according to the present embodiment will be described. The model of the example is the washer 6 shown in the above-described embodiment, and the model of the comparative example is a washer in which the oil grooves 6f shown in FIG. In addition, the dimensions of each part other than the arrangement of the oil groove 6f are all set to be the same. Then, when these were actually used in the cross joint 1, FEM analysis was performed by CAE or the like to compare the stress distribution of the washer.

FIG. 4 is a graph showing the results of the stress analysis as numerical values for each part of the washer. In the figure, the vertical axis indicates the stress value, and the horizontal axis indicates the portion of the washer (the inner periphery, the center, and the outer periphery). In the figure, in the inner peripheral edge, the model of the example has a stress value smaller than that of the model of the comparative example. On the contrary, in the central portion, the model of the example is larger than the model of the comparative example, and it can be confirmed that the stress is increased due to the rigidity decrease at the intersection K. At the outer peripheral edge, the model of the example is slightly smaller than the model of the comparative example.
Thus, it can be seen that the stress distribution of the model of the example is improved from the inner peripheral edge portion to the outer peripheral edge portion so as to have a uniform stress value as a whole as compared with the comparative product.

  As described above, the oil groove 6f is formed so that the oil groove 6f on the washer end surface 6b side and the oil groove 6f on the washer end surface 6c side have the intersecting portion K intersecting each other, whereby the stress distribution of the washer 6 is obtained. As a whole, it was confirmed that it can be made relatively uniform.

  The thrust washer of the present invention and the cross joint using the same are not limited to the above embodiment. For example, the oil groove 6f does not have to be linearly extended at the end face of the washer 6, and is curved if the intersecting portion K is located in the middle between the inner peripheral edge 6d and the outer peripheral edge 6e. It is good also as a shape. Moreover, although the cross-sectional shape of the oil groove 6f is concave, for example, the cross-sectional shape may be semicircular in order to prevent stress concentration. Further, the configuration of the cross joint 1 and the material and shape of the thrust washer can be appropriately changed based on the gist of the present invention.

It is a partial cross section figure of the cross joint using the thrust washer for cross joints which is one Embodiment of this invention. (A) is a top view of a thrust washer, (b) has shown the side view of a thrust washer. It is a top view which shows arrangement | positioning of the oil groove of the thrust washer used as the model of the comparative example. It is the graph which showed the result of having performed stress analysis as a numerical value for every part of a thrust washer.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Cross shaft joint 2 Shaft part 3 Cross shaft 4 Bearing cup 6 Thrust washer 6a Through-hole 6b, 6c Washer end surface 6d Inner periphery 6e Outer periphery 6f Oil groove (groove part)

Claims (2)

A thrust washer for a cross shaft joint having a disc-like shape with a through hole formed in the center thereof, and a plurality of grooves extending from the inner peripheral edge on the through hole side toward the outer peripheral edge. In
When the groove portion formed on the one side end surface and the groove portion formed on the other side end surface are viewed in plan from the end surface , they intersect at an approximately center between the outer peripheral edge and the inner peripheral edge ,
When the inner peripheral edge side end portion of the groove portion formed on the one end surface and the inner peripheral edge side end portion of the groove portion formed on the other end surface are viewed from the end surface, the inner peripheral edge Are arranged alternately and at substantially equal pitches in the circumferential direction of
The outer peripheral edge side end of the groove formed on the one end face and the outer peripheral edge end of the groove formed on the other end face do not overlap when viewed from the end face in plan view. A thrust washer characterized by being alternately arranged in the circumferential direction of the peripheral edge . A cross shaft having four shaft portions arranged in a cross shape, a bottomed cylindrical bearing cup rotatably attached to these shaft portions, a through hole is formed in the center thereof, and both end faces thereof A plurality of groove portions extending from the inner peripheral edge on the through hole side toward the outer peripheral edge are formed, and a disc-shaped thrust washer disposed between the bottom surface of the bearing cup and the end surface of the shaft portion. In the cross shaft joint provided,
The cross shaft joint according to claim 1 , wherein the thrust washer is a thrust washer according to claim 1 .

Images