JPH0235052Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention relates to a constant velocity universal joint mainly applied to front-wheel drive automobiles, and in particular to a tripod type constant velocity universal joint.

[Prior art]

As a conventional constant velocity universal joint of this kind, for example, as shown in FIG. A radial leg shaft 4 is provided protruding from each leg shaft 4, and a spherical roller 5 is rotatably and axially slidably fitted on the outside of each leg shaft 4. It is known to engage the roller guide surface 6 of the roller.

In the tripod type constant velocity universal joint described above, if we consider the case where rotational force is transmitted in a state where the outer ring 1 and the tripod member 3 take an operating angle, each spherical roller 5
and the roller guide surface 6 of the cylindrical track groove 2 are in an oblique relationship with each other as shown in FIGS. 15 and 16, and the spherical roller 5 cannot be caused to roll correctly. That is, the spherical roller 5 tries to roll and move in the direction shown by arrow A in FIG. It will move while being restrained by the groove 2. As a result, a slip occurs between the roller guide surface 6 of the track groove 2 and the spherical roller 5, generating heat. Furthermore, this slip induces a thrust force in the axial direction, causing vibration.

The inventors of the present invention found that if the track grooves 2 were made cylindrical and the rollers 5 were made spherical, the above-mentioned problems would occur, and in order to solve the problems, various studies were carried out. Since the rollers move without being restrained, we thought that the above-mentioned problems could be solved by making the roller guide surface 6 of the track groove 2 flat and making the roller 5 cylindrical. However, in a configuration in which the cylindrical roller is simply fitted to the leg shaft of the tripod member, when the shaft on the outer ring side and the axis of the tripod member take an operating angle, interference occurs between the outer peripheral surface of the cylindrical roller and the roller guide surface. This causes so-called kinking, and the joint cannot function as a universal joint.

That is, as schematically shown in FIG. 14, the tripod member 3 uses the contact point of the rollers 5a, 5b fitted to the two leg shafts 4a, 4b as a fulcrum, and the roller of the other leg shaft 4c. 5c and the axis o, and if the axis o moves to o' and swings around the axis o with a radius r, then the two leg axes 4a and 4b produces a deviation by an angle r compared to the case where the operating angle is 0 degrees. Therefore, the leg axis 4
Interference occurs between the outer circumferential portions of the cylindrical rollers 5a and 5b fitted to the rollers a and 4b and the roller guide surface 6, as shown by the chain line B, and the function of the constant velocity universal joint cannot be achieved.

[Problem for invention]

The technical challenge of this invention is to solve the problems of conventional tripod type constant velocity universal joints, and to prevent the generation of heat and vibration by ensuring that the rollers fitted in the track grooves roll correctly. .

[Structure of the idea]

In order to solve the above problems, this invention makes the roller guide surfaces on both sides of the track groove provided on the inner surface of the outer ring a plane parallel to the plane containing the axis of the outer ring and the center of the track groove, and makes the roller cylindrical. , a ring is interposed between the cylindrical roller and the leg shaft, and the ring is supported rotatably about an axis perpendicular to the axis of the leg shaft and parallel to the axis of the tripod member, and The structure is such that it is supported so as not to rotate within the plane formed by the axis and the axis of the leg shaft.

[Effect]

In the constant velocity universal joint with the above configuration, power is transmitted by the engagement of the roller guide surface and the cylindrical roller, similar to the conventional constant velocity universal joint, and for plunging, the cylindrical roller is connected to the roller. It rolls along the guide surface and absorbs this.

When the axis of the outer ring and the axis of the tripod member are on the same axis, that is, when the operating angle is 0 degrees, in power transmission, the intersection of the axis of each leg axis is on the axis of the outer ring. Because of this position, the cylindrical roller is held in line contact with the roller guide surface, and no rotational adjustment force is generated on the ring.

When an operating angle occurs, the intersection point of the axes of the leg shafts deviates from the axis of the outer ring, so it moves circularly around the axis of the outer ring with a radius corresponding to the deviation,
This causes vibration in the leg axis. Due to this swing of the leg axis,
The contact of the cylindrical roller with the roller guide surface tends to change from a line contact to a point contact, and the reaction force that the cylindrical roller receives from the roller guide surface becomes biased, and a rotation adjustment force is generated in the ring. Therefore, the ring rotates by a required angle in response to the runout of the axis of the cylindrical roller, and absorbs interference between the cylindrical roller and the roller guide surface.

〔Example〕

Hereinafter, embodiments of this invention will be described based on the accompanying drawings.

As shown in FIGS. 1 to 3, the outer ring 10 has a first shaft 11 integrally provided at the closed end as in the conventional case, and three track grooves 12 in the axial direction on the inner circumferential surface. They are formed at 120 degree intervals around the axis. Each track groove 12 has two roller guide surfaces 13 on both sides.
3 is a plane parallel to a plane containing the axis of the outer ring 10 and the center of the track groove 12.

The tripod member 14 inserted into the outer ring 10 is engaged with a serration 16 formed at one end of the second shaft 15, and is held in place between the stepped portion 17 and the clip 18. . This tripod member 14 has three leg shafts 19, and a pair of flat surfaces 20 parallel to a plane perpendicular to the axis of the tripod member 14 on the outer peripheral surface of each leg shaft 19.
and a cylindrical surface 21 having an axis parallel to the axis of the tripod member 14. This leg shaft 19
The leg shaft insertion hole 23 of the ring 22 fitted around the
is a square hole, and among the opposing inner surfaces of the insertion hole 23, one inner surface engages with the flat surface 20, and the other inner surface is in line contact with the cylindrical surface 21. Therefore, the ring 22 does not rotate within a plane defined by the axis of the tripod member 14 and the axis of the leg shaft 19, but can rotate along the cylindrical surface 21.

Further, a cylindrical roller 24 is provided around the ring 22.
A rolling element 25 is installed between the cylindrical roller 24 and the ring 22. This cylindrical roller 24 is prevented from coming off by retaining rings 26 attached to the outer periphery of both ends of the ring 22.

The constant velocity universal joint shown in the embodiment has the above structure, and its operation will be explained next.

When the operating angle between the first shaft 11 and the second shaft 15 is 0 degrees, the rotation between them is transmitted via the roller guide surface 13 of the track groove 12 and the cylindrical roller 24 engaged therewith. In this case, when plunging occurs due to relative movement between the two, the cylindrical roller 24 rotates around the ring 22 and rolls along the flat roller guide surface 13 of the track groove 12. At this time, the outer peripheral surface of the cylindrical roller 24 is
Since the cylindrical roller 24 is in line contact with the ring 22 and receives a uniform reaction force on the line of contact, no rotation adjustment force is generated in the ring 22.

Further, when an operating angle occurs between the first shaft 11 and the second shaft 15, the leg shaft 19 rotates around the axis of the second shaft 15, and at the time of rotation, the leg shaft 19 rotates around the axis of the second shaft 15.
As shown in the figure, runout occurs, and due to the runout, the contact of the cylindrical roller 24 with the roller guide surface 13 tends to change from line contact to point contact, and the reaction force that the cylindrical roller 24 receives from the roller guide surface 13 is on the contact line. lean to one end of the The reaction force can be shown by the arrow a in FIG. 5, and the reaction force acts at a position perpendicular to the axis of the leg shaft 19 and a distance c from the plane b containing the axis of the cylindrical surface 21. , the ring 22 receives a rotation adjustment force around the axis of the cylindrical surface 21, the ring 22 rotates by a rotation angle β to absorb the above reaction force, and the cylindrical roller 24 rotates along the flat roller guide surface 13. Roll.

In the embodiment shown in FIGS. 1 to 3, the leg shaft 19
Simply fit the ring 22 onto the outside of the leg shaft 19.
Although this is an example in which the ring 22 is supported movably in the axial direction, the ring 22 may be supported non-movably in the axial direction.

6 to 11 show an example in which the ring 22 is supported immovably in the axial direction.

6 and 7, a leaf spring 30 is attached to both ends of the leg shaft 19, and both ends of the leaf spring 30 are engaged with both end surfaces of the ring 22 to prevent the ring 22 from coming off. There is.

8 and 9, a pin insertion hole 31 passing through the axis of the cylindrical surface 21 of the leg shaft 19 is formed in the leg shaft 19 and the ring 22 on the outside thereof.
A pin 32 is inserted into the ring 1 and the ring 22 is rotatably supported around the pin 32. In this case, when the pin insertion hole 31 of the leg shaft 19 and the pin 32 are loosely fitted, the cylindrical surface 21 becomes the pressure receiving surface, and when the leg shaft insertion hole 23 and the cylindrical surface 21 are loosely fitted, the pin 32 becomes the pressure receiving surface. It becomes a pressure receiving part.

10 and 11 show that a spacer 33 is incorporated between the leg shaft insertion hole 23 of the ring 22 and the cylindrical surface 21, and a retaining ring 34 is attached to both ends of the inner peripheral surface of the leg shaft insertion hole 23. The spacer 33 is held there.

13 and 14 show other embodiments of the constant velocity universal joint. In this constant velocity universal joint, the outer periphery of the leg shaft 19 is a toroidal surface 35, and a tripod member 1 is placed at a position opposite to the toroidal surface 35.
Flat surface 2 parallel to the plane perpendicular to the axis of 4
0 is set. Further, the leg shaft insertion hole 23 of the ring 22 fitted around the leg shaft 19 is provided with a cylindrical surface 36 centered on the axis of the leg shaft 19, facing the toroid surface 35.

In this case as well, similarly to the constant velocity universal joint shown in FIGS. 1 to 3, when the operating angle is 0 degrees, the leg shaft 19
No rotation adjustment force is generated around a straight line parallel to the axis of the tripod member 14 through the center of the toroid surface 35 of the ring 22, but when an operating angle occurs, a rotation adjustment force is generated to move the ring 22 around the straight line. It rotates by a required rotation angle and absorbs interference with the roller guide surface 13.

〔effect〕

As described above, according to the constant velocity universal joint according to this invention, it is possible to prevent the ring installed between the leg shaft and the cylindrical roller from swinging in the axial direction of the tripod member, and to prevent the ring from swinging in the axial direction. Since the roller guide surface of the track groove that guides the movement of the cylindrical roller is made flat, the cylindrical roller can be moved to the roller guide surface when the constant velocity universal joint is transmitting torque that takes an operating angle. It can be kept in line contact at all times. Therefore, the cylindrical roller can be made to roll over almost the entire area of the large roller guide surface by contact with the roller guide surface, and as a result, the sliding resistance is extremely small, and the contact area with the roller guide surface is It is possible to prevent seizure due to lack of oil film, and to prevent vibration and heat generation.

In addition, when transmitting torque that takes an operating angle, the cylindrical roller tilts in the same direction as the leg shaft, so there is no relative movement in the leg shaft direction between the cylindrical roller and the leg shaft.
Since no guide means is required to absorb the movement, the configuration can be simplified, and
Since the roller guide surface is flat, processing is easy.

Furthermore, if the cylindrical roller is swingable in any direction, the cylindrical roller will interfere with the outer diameter surface of the track groove during torque transmission, producing interference noise. Since the swing of the head is restricted, interference noise can be prevented from occurring.

[Brief explanation of the drawing]

Fig. 1 is a longitudinal sectional front view showing one embodiment of the constant velocity universal joint according to the invention, Fig. 2 is a longitudinal sectional side view of the same, Fig. 3 is an exploded perspective view of the same tripod member, and Fig. 4 is FIG. 5 is an explanatory diagram of the operation of the cylindrical roller and the ring. FIGS. 6 to 11 are diagrams showing the state in which the cylindrical roller and the ring are connected. FIG. A plan view, FIG. 7 is a vertical front view, FIG. 8 is a cross-sectional plan view, FIG. 9 is a vertical front view, FIG. 10 is a plan view, FIG. 11 is a vertical front view, and FIG. A partially cutaway plan view showing another embodiment, FIG. 13 is a longitudinal sectional front view of the same as above,
FIG. 14 is a schematic diagram for explaining the problem, FIG. 15 is a longitudinal cross-sectional side view showing the conventional vertical direction, and FIG. 16 is a perspective view showing the rolling state of the same spherical roller. 10... Outer ring, 12... Track groove, 13...
Roller guide surface, 14...Tripod member, 19...
...Leg shaft, 22...Ring, 24...Cylindrical roller.

Claims (1)

[Claims for Utility Model Registration] (1) Three track grooves in the axial direction are formed on the inner surface of the outer ring, and three leg shafts are provided protruding from the tripod member disposed inside the outer ring. In a constant velocity universal joint in which a roller fitted on the outside of the track groove is disposed between the roller guide surfaces on both sides of the track groove to transmit rotational motion between the outer ring and the tripod member, the roller guide surface of the track groove is The plane is parallel to the plane containing the axis of the outer ring and the center of the track groove, the roller is cylindrical, a ring is interposed between the cylindrical roller and the leg shaft, and this ring is perpendicular to the axis of the leg shaft. and is characterized in that it is supported rotatably about an axis parallel to the axis of the tripod member and is supported so as not to rotate within a plane formed by the axis of the tripod member and the axis of the leg shaft, etc. Quick universal joint. (2) On the outer periphery of the leg shaft, a flat surface parallel to a plane perpendicular to the axis of the tripod member, and a cylindrical surface having an axis perpendicular to the axis of the leg shaft and parallel to the axis of the tripod member. or a toroidal surface, and a surface that engages with the flat surface and a surface that contacts the cylindrical surface or toroidal surface are provided on the inner surface of the leg shaft insertion hole of the ring fitted on the outside of the leg shaft. A constant velocity universal joint according to claim 1 of the utility model registration claim, characterized in that: (3) The constant velocity universal joint according to claim 1 or 2, wherein the axial movement of the leg shaft of the ring is restricted. (4) The constant velocity universal joint according to claim 1, 2, or 3 of the utility model registration, characterized in that a rolling element is interposed between the ring and the cylindrical roller.