Tripod type constant velocity universal joint

Abstract

In this tripod-type constant-velocity universal joint (1), the groove orthogonal cross-sectional shape of a ceiling surface (13) of a raceway groove (10) in an outer ring (2) is formed by a line shape that passes through a central highest point (P1, P11, P12), a positive-rotation highest edge point (P2, P13, P15), and a reverse-rotation highest edge point (P3, P14, P16). The central highest point (P1, P11, P12) is a point reached when a roller (4) is pitched by only a prescribed pitching angle (θp2). The forward-rotation highest edge point (P2, P13, P15) is a point reached when the roller (4) has rolled in positive rotation by only a prescribed rolling angle (θr11). The reverse-rotation highest edge point (P3, P14, P16) is a point reached when the roller (4) has rolled in reverse rotation by only a prescribed rolling angle (θr12).

Description

[Technical Field]

[0001] The present disclosure relates to a tripod-type constant velocity universal joint. [Background technology]

[0002] The tripod-type constant velocity universal joint described in Patent Document 1 is configured to suppress tilting of the rollers by the raceway grooves of the outer ring. The tilting of the rollers is suppressed by a part of the ceiling surface of the raceway grooves of the outer ring coming into contact with the end faces of the rollers. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2016-130533 Summary of the Invention [Problem to be solved by the invention]

[0004] It is known that the rollers of a tripod-type constant velocity universal joint may pitch or roll as the joint operates. However, in the tripod-type constant velocity universal joint described in Patent Document 1, the tilting of the rollers is restricted by the ceiling surface of the raceway groove. Therefore, when the rollers attempt to pitch or roll, friction occurs due to contact between the ceiling surface of the raceway groove of the outer ring and the end surface of the roller. This friction causes a forcing force that induces vibration in the tripod-type constant velocity universal joint.

[0005] The present disclosure has been made in consideration of such problems, and aims to provide a tripod-type constant velocity universal joint that can suppress the generation of force by preventing the roller end faces from contacting the ceiling surface of the raceway groove of the outer ring, at least within a certain angular range. [Means for solving the problem]

[0006] One aspect of the present disclosure is a bearing comprising: an outer ring having a plurality of raceway grooves extending in an axial direction; a tripod including a plurality of tripod shaft portions extending radially outward; rollers fitted onto the tripod shaft portions and rolling in the raceway grooves; A tripod-type constant velocity universal joint comprising: the raceway groove includes a first raceway surface constituting one of the groove side surfaces, a second raceway surface constituting the other of the groove side surfaces, and a ceiling surface constituting the groove bottom surface, The roller is a roller outer peripheral surface configured to be able to roll on the first raceway surface or the second raceway surface; an axial end surface of the roller that faces the ceiling surface; Equipped with a point on a contour line obtained by projecting the roller end face in the axial direction of the outer ring when the roller is pitched by a predetermined pitching angle, the point being located on the central axis of the roller and farther from the central axis of the outer ring, is defined as the central highest point; a boundary point between the outer peripheral surface of the roller and the roller end surface, which is located farther from the central axis of the outer ring, on a contour line obtained by projecting the roller in the axial direction of the outer ring when the roller rolls in a forward rotation direction by a predetermined rolling angle, is defined as the highest point of the forward rotation edge; a boundary point between the roller outer peripheral surface and the roller end surface located farther from the central axis of the outer ring on a contour line obtained by projecting the roller in the axial direction of the outer ring when the roller has rolled in a reverse rotation direction by a predetermined rolling angle, the boundary point being the highest point of the reverse rotation edge; In a tripod-type constant velocity universal joint, the orthogonal cross-sectional shape of the groove on the ceiling surface is formed by a line shape passing through the center highest point, the positive rotating edge highest point, and the reverse rotating edge highest point. [Effects of the Invention]

[0007] In the tripod-type constant velocity universal joint of the above aspect, the groove orthogonal cross-sectional shape of the ceiling surface of the raceway groove of the outer ring is formed by a line shape passing through the center highest point, the forward rotation edge highest point, and the reverse rotation edge highest point. The center highest point is a point obtained from the contour line of the roller end surface when the roller pitches by a predetermined pitch angle. The forward rotation edge highest point is a point obtained from the contour line of the roller when the roller rolls in a forward rotation direction by a predetermined roll angle. The reverse rotation edge highest point is a point obtained from the contour line of the roller when the roller rolls in a reverse rotation direction by a predetermined roll angle.

[0008] Therefore, when the roller pitches an angle smaller than the predetermined pitch angle, or when the roller rolls an angle smaller than the predetermined roll angle, the roller can be prevented from contacting the ceiling surface of the raceway groove of the outer ring. In this way, as long as the pitching and rolling of the roller is within at least a certain angular range, the roller end face can be prevented from contacting the ceiling surface of the raceway groove of the outer ring, and the generation of a forcing force can be suppressed.

[0009] In particular, the central highest point is the point on the central axis of the roller and located farther from the central axis of the outer ring on the contour line obtained by projecting the roller end face in the axial direction of the outer ring when the roller pitches by a predetermined pitch angle. The positive rotation edge highest point is the boundary point between the roller outer peripheral surface and the roller end face located farther from the central axis of the outer ring on the contour line obtained by projecting the roller in the axial direction of the outer ring when the roller rolls in the forward direction by a predetermined roll angle. The reverse rotation edge highest point is the boundary point between the roller outer peripheral surface and the roller end face located farther from the central axis of the outer ring on the contour line obtained by projecting the roller in the axial direction of the outer ring when the roller rolls in the reverse direction by a predetermined roll angle.

[0010] In this way, the shape of the ceiling surface is defined by considering which position on the cross section perpendicular to the groove of the ceiling surface approaches which point on the roller during pitching and rolling. By configuring in this way, as long as the pitching and rolling of the roller is within at least a certain angular range, the roller end face can be prevented from contacting the ceiling surface of the raceway groove of the outer ring, thereby suppressing the generation of a forcing force.

[0011] As described above, according to the above aspect, it is possible to provide a tripod-type constant velocity universal joint that can suppress the generation of a force by preventing the roller end faces from contacting the ceiling surface of the raceway groove of the outer ring at least within a certain angular range.

[0012] It should be noted that the reference numerals in parentheses in the claims indicate the correspondence with the specific means described in the embodiments to be described later, and do not limit the technical scope of the present invention. [Brief explanation of the drawings]

[0013] [Figure 1] 1 is a view of the tripod type constant velocity universal joint of the first embodiment as seen from the axial direction, showing the case where the joint angle is 0°, and showing only one raceway groove portion of the outer ring. FIG. [Figure 2] 2 is a cross-sectional view taken along line II-II in FIG. 1, and is a partial cross-sectional view taken along the axial direction of the tripod constant velocity universal joint. [Figure 3] 3 is a cross-sectional view taken along line III-III in FIG. 2, and is a partial cross-sectional view in the radial direction of the tripod type constant velocity universal joint. [Figure 4] FIG. 10 is a partial view of the tripod constant velocity universal joint as viewed from the axial direction when the joint angle is θp1 and the rollers pitch by the pitching angle θp1. [Figure 5] FIG. 5 is a VV cross-sectional view of FIG. 4, and is a partial cross-sectional view taken along the axial direction of the tripod constant velocity universal joint when the joint angle is θp1. [Figure 6]FIG. 10 is a partial view of the tripod constant velocity universal joint as viewed from the axial direction when the joint angle is 0° and the rollers roll in the forward direction by a rolling angle θr1. [Figure 7] FIG. 10 is a partial view of the tripod constant velocity universal joint as viewed from the axial direction when the joint angle is 0° and the rollers are rolling in the reverse direction by a rolling angle θr2. [Figure 8] 10 is a partial axial cross-sectional view of a tripod-type constant velocity universal joint when the joint angle is θp2 and the rollers are pitched by the pitching angle θp2. FIG. [Figure 9] FIG. 8 is a view from the left side of FIG. 7, that is, a view from the axial direction of the outer ring, showing only the outer ring and rollers. [Figure 10] FIG. 10 is a partial view of the tripod constant velocity universal joint as viewed from the axial direction when the joint angle is 0° and the rollers roll in the forward direction by a rolling angle θr11. [Figure 11] FIG. 10 is a partial view of the tripod constant velocity universal joint as viewed from the axial direction when the joint angle is 0° and the rollers are rolling in the reverse direction by a rolling angle θr12. [Figure 12] FIG. 4 is a diagram showing a cross-sectional shape of a ceiling surface of a raceway groove of an outer ring, the cross-sectional shape being perpendicular to the groove. [Figure 13] FIG. 10 is a partial view of the tripod type constant velocity universal joint of the second embodiment, seen from the axial direction when the rollers pitch by a pitching angle θp2 and contact the first raceway surface. [Figure 14] FIG. 10 is a partial view of the tripod type constant velocity universal joint of the second embodiment, seen from the axial direction when the rollers pitch by a pitching angle θp2 and contact the second raceway surface. [Figure 15] FIG. 10 is a partial view of the tripod constant velocity universal joint viewed from the axial direction when the joint angle is 0°, the rollers roll in the forward direction through a roll angle θr11, and the rollers contact the first raceway surface. [Figure 16]This is a partial view of the tripod constant velocity universal joint as seen from the axial direction when the joint angle is 0°, the rollers roll in the reverse direction by a roll angle θr12, and the rollers contact the second raceway surface. [Figure 17] FIG. 4 is a diagram showing a cross-sectional shape of a ceiling surface of a raceway groove of an outer ring, the cross-sectional shape being perpendicular to the groove. [Figure 18] FIG. 11 is a partial view of the tripod type constant velocity universal joint of embodiment 3, viewed from the axial direction, when the joint angle is 0°, the rollers are rolling in the forward direction by a rolling angle θr11, and the rollers are in contact with the second raceway surface. [Figure 19] FIG. 11 is a partial view of the tripod type constant velocity universal joint of embodiment 3, viewed from the axial direction, when the joint angle is 0°, the rollers are rolling in the reverse direction by a rolling angle θr12, and the rollers are in contact with the first raceway surface. [Figure 20] FIG. 4 is a diagram showing a cross-sectional shape of a ceiling surface of a raceway groove of an outer ring, the cross-sectional shape being perpendicular to the groove. [Figure 21] 10 is a view showing the cross-sectional shape of a ceiling surface of a raceway groove of an outer ring in a tripod type constant velocity universal joint of a fourth embodiment taken along a plane perpendicular to the groove. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0014] (Embodiment 1) 1. Structure of tripod-type constant velocity universal joint 1 The configuration of a tripod type constant velocity universal joint 1 of this embodiment will be described with reference to Fig. 1 to Fig. 3. The tripod type constant velocity universal joint 1 is used, for example, in a drive shaft or propeller shaft of a vehicle. The tripod type constant velocity universal joint 1 includes an outer ring 2, tripods 3, and rollers 4.

[0015] The outer ring 2 is formed in a cylindrical shape with a bottom, and has three raceway grooves 10 extending axially on its inner peripheral surface. The three raceway grooves 10 are positioned at equal intervals in the circumferential direction. However, Figs. 1 to 3 only show one raceway groove 10. In the following, a groove-orthogonal cross section is a cross section perpendicular to the direction in which the raceway grooves 10 extend, and a groove-direction cross section is a cross section in the direction in which the raceway grooves 10 extend. Furthermore, a line that is perpendicular to the central axis Lo of the outer ring 2 and that passes through the center of the raceway groove 10 in the groove width direction is referred to as a raceway groove centerline Lg.

[0016] The raceway groove 10 has a first raceway surface 11 constituting one groove side surface and a second raceway surface 12 constituting the other groove side surface. The first raceway surface 11 and the second raceway surface 12 face each other. The groove-orthogonal cross-sectional shapes of the first raceway surface 11 and the second raceway surface 12 are formed into a curved concave shape in the groove-orthogonal cross-section of the raceway groove 10. The groove-orthogonal cross-sectional shapes of the first raceway surface 11 and the second raceway surface 12 are formed into, for example, a Gothic arc shape formed by connecting two circular arcs.

[0017] The raceway groove 10 further includes a ceiling surface 13 that forms the groove bottom surface. The detailed shape of the ceiling surface 13 will be described later. Furthermore, in this embodiment, the raceway groove 10 includes a first recessed surface 14 and a second recessed surface 15. The first recessed surface 14 is a portion that connects the first raceway surface 11 and the ceiling surface 13, and is located at one of the groove bottom corners. The second recessed surface 15 is a portion that connects the second raceway surface 12 and the ceiling surface 13, and is located at the other of the groove bottom corners. The groove orthogonal cross-sectional shapes of the first recessed surface 14 and the second recessed surface 15 are formed into a curved concave shape with a smaller radius of curvature than the first raceway surface 11, the second raceway surface 12, and the ceiling surface 13.

[0018] The tripod 3 is a member attached to a shaft (not shown) and constitutes an inner member housed inside the outer ring 2. The tripod 3 includes a boss portion 21 and three tripod shaft portions 22. The boss portion 21 is formed in a cylindrical shape, and has a spline formed on its inner peripheral surface that is configured to be able to fit onto the shaft.

[0019] The tripod-shaft portions 22 are shaft members extending radially outward from the outer circumferential surface of the boss portion 21. The tripod-shaft portions 22 are formed in a columnar shape, a spherical shape, or the like. For example, the tripod-shaft portions 22 formed in a columnar shape may be a circular cylinder, an elliptical cylinder, or a composite columnar shape in which a portion of a circular cylinder or an elliptical cylinder is formed into a flat shape. In this embodiment, the columnar cross-sectional shape of the tripod-shaft portions 22 includes a pair of convex curved portions that form a portion of an ellipse, and a straight portion that connects the convex curved portions.

[0020] The rollers 4 are fitted onto the tripod-shaft portions 22 and are slidable in the axial direction of the tripod-shaft portions 22. In a state where the rollers 4 are fitted onto the tripod-shaft portions 22, the rollers 4 roll in the raceway grooves 10 of the outer ring 2. When transmitting torque between the rollers 4 and the first raceway surfaces 11, the rollers 4 roll on the first raceway surfaces 11. On the other hand, when transmitting torque between the rollers 4 and the second raceway surfaces 12, the rollers 4 roll on the second raceway surfaces 12.

[0021] 1 and 2, the outer shape of the roller 4 has a roller outer circumferential surface 31, roller end surfaces 32, and a roller root surface 33. The roller outer circumferential surface 31 is configured to be able to roll on the first raceway surface 11 or the second raceway surface 12. The roller outer circumferential surface 31 is formed, for example, in a spherical shape centered on a point on the central axis Lr of the roller 4.

[0022] The roller end surface 32 is the surface of the axial end surface of the roller 4 that faces the ceiling surface 13. In this embodiment, the roller end surface 32 includes a circular flat portion 32a and a chamfered portion 32b. The circular flat portion 32a is formed in a disk shape that is centered on the central axis Lr of the roller 4 and parallel to a plane perpendicular to the axis of the roller 4. The chamfered portion 32b is a surface that connects the outer peripheral edge of the circular flat portion 32a to the roller outer peripheral surface 31, and is formed in a partial conical shape that is inclined with respect to the plane perpendicular to the axis of the roller 4.

[0023] The roller root surface 33 is the surface of the axial end surface of the roller 4 facing away from the roller end surface 32. In this embodiment, the roller root surface 33 is formed in a plane symmetrical to the roller end surface 32. The roller root surface 33 includes a circular flat portion 33a and a chamfered portion 33b. The circular flat portion 33a is formed in a disk shape centered on the central axis Lr of the roller 4 and parallel to a plane perpendicular to the axis of the roller 4. The chamfered portion 33b is a surface connecting the outer peripheral edge of the circular flat portion 33a to the roller outer peripheral surface 31, and is formed in a partial conical shape inclined with respect to the plane perpendicular to the axis of the roller 4.

[0024] The rollers 4 may be either a single roller type or a double roller type. For example, a single roller type roller 4 is configured with an outer roller and a plurality of needle bearings arranged between the outer peripheral surface of the tripod shaft portions 22 and the inner peripheral surface of the outer roller. A double roller type roller 4 is configured with an outer roller, an inner roller, and a plurality of needle bearings arranged between the outer roller and the inner roller. Furthermore, the rollers 4 may be configured to be tiltable or non-tiltable relative to the tripod shaft portions 22.

[0025] In this embodiment, the roller 4 is configured as a double roller type as shown in Fig. 3. The roller 4 is configured with an outer roller 41, an inner roller 42, a plurality of needle bearings 43, and retaining rings 44 and 45. The outer peripheral surface of the outer roller 41 is configured to be able to roll on the first raceway surface 11 and the second raceway surface 12.

[0026] The axial cross-sectional shape of the inner peripheral surface of the inner roller 42 is formed, for example, in a convex curve facing radially inward. The inner roller 42 is fitted onto the outer peripheral surface of the tripod-shaft portion 22 and is tiltable relative to the tripod-shaft portion 22. A plurality of needle bearings 43 are interposed between the inner peripheral surface of the outer roller 41 and the outer peripheral surface of the inner roller 42. Retaining rings 44, 45 are engaged with the outer roller 41 and engage with the inner roller 42 and the plurality of needle bearings 43 to position the inner roller 42 and the plurality of needle bearings 43.

[0027] 2. Operation of tripod-type constant velocity universal joint 1 The operation of the tripod-type constant velocity universal joint 1 will be described with reference to Figs. 4 to 7. As shown in Figs. 4 and 5, the angle formed between the central axis Lo of the outer ring 2 and the central axis of the tripod 3 is the joint angle. Furthermore, when the central axis Lr of the roller 4 coincides with the central axis of the tripod-shaft portion 22, the angle formed between the raceway groove center line Lg and the central axis Lr of the roller 4 is equal to the joint angle. Figs. 4 and 5 show a state in which the joint angle is θp1.

[0028] When the joint angle is θp1, when the tripod constant velocity universal joint 1 rotates, torque is transmitted between the outer ring 2 and the tripod 3 via the rollers 4. At this time, the rollers 4 roll on the first raceway surface 11 or the second raceway surface 12 while performing a pitching motion relative to the raceway groove 10, and move back and forth in the raceway groove 10.

[0029] Furthermore, the positions of the tripod-shaft portions 22 that come into contact with the rollers 4 move in the axial direction of the tripod-shaft portions 22. Therefore, as shown in FIG. 6, the rollers 4 perform forward rolling, and as shown in FIG. 7, the rollers 4 perform reverse rolling. In FIG. 6, the rolling angle during forward rolling is θr1, and in FIG. 7, the rolling angle during reverse rolling is θr2. The rolling angle θr1 is the angle between the raceway groove center line Lg and the central axis Lr of the roller 4 during forward rolling. The rolling angle θr2 is the angle between the raceway groove center line Lg and the central axis Lr of the roller 4 during reverse rolling.

[0030] Here, the maximum joint angle φ1 of the tripod type constant velocity universal joint 1 when the vehicle is traveling straight at a constant speed is an angle that falls within the range of 4 to 10°, for example. The maximum joint angle φ2 of the tripod type constant velocity universal joint 1 when the vehicle is accelerating or decelerating when traveling straight can take an angle range larger than the maximum joint angle φ1. The maximum joint angle φ2 falls within the range of 6 to 20°, for example. The maximum joint angle φ3 of the tripod type constant velocity universal joint 1 when the vehicle is turning at maximum speed can take an angle range larger than the maximum joint angles φ1 and φ2. The maximum joint angle φ3 falls within the range of 10 to 25°, for example.

[0031] Furthermore, the maximum rolling angle φ11 of the roller 4 when the vehicle is traveling straight at a constant speed is, for example, an angle within the range of 0 to 5°. The maximum rolling angle φ12 of the roller 4 when the vehicle is accelerating or decelerating while traveling straight is, for example, within the range of 0 to 5°. The maximum rolling angle φ13 of the roller 4 when the vehicle is turning at maximum speed can have an angle range larger than the maximum rolling angles φ11 and φ12. The maximum rolling angle φ13 is, for example, within the range of 0 to 10°.

[0032] 3. Outline of the cross-sectional shape of the groove at right angles on the ceiling surface 13 The outline of the groove orthogonal cross-sectional shape of the ceiling surface 13 of the raceway groove 10 of the outer ring 2 will be explained with reference to Figs. 8 to 11. The groove orthogonal cross-sectional shape of the ceiling surface 13 is determined using the shape of the roller 4 when the roller 4 pitches by a predetermined pitching angle θp2, as shown in Fig. 8. When the roller 4 pitches by the predetermined pitching angle θp2, the roller 4 appears as shown in Fig. 7 when viewed from the axial direction of the outer ring 2. The predetermined pitching angle θp2 is the contact pitching angle. This means that the roller 4 can come into contact with the ceiling surface 13 when the roller 4 pitches by the predetermined angle θp2.

[0033] Furthermore, as shown in FIG. 10, the groove orthogonal cross-sectional shape of the top surface 13 is determined using the shape of the roller 4 when it rolls in a forward direction by a predetermined rolling angle θr11. Also, as shown in FIG. 11, the groove orthogonal cross-sectional shape of the top surface 13 is determined using the shape of the roller 4 when it rolls in a reverse direction by a predetermined rolling angle θr12. The predetermined rolling angles θr11 and θr12 are contact rolling angles. This means that the roller 4 can come into contact with the top surface 13 when it rolls in a forward direction by the predetermined rolling angle θr11 or when it rolls in a reverse direction by the predetermined rolling angle θr12. The rolling angle θr11 is the angle between the raceway groove center line Lg and the central axis Lr of the roller 4 when it rolls in a forward direction. The rolling angle θr12 is the angle between the raceway groove center line Lg and the central axis Lr of the roller 4 when it rolls in a reverse direction.

[0034] The predetermined pitching angle θp2 can be set to one of the following two angles. The first predetermined pitching angle θp2 is set to an angle that is larger than the maximum joint angle φ1 when the vehicle is traveling straight and at a constant speed, and is equal to or smaller than the maximum joint angle φ2 when the vehicle is accelerating or decelerating while traveling straight. In this case, the first predetermined pitching angle θp2 is naturally set to an angle that is smaller than the maximum joint angle φ3 when the vehicle is turning at maximum speed.

[0035] In this case, when the pitching angle of roller 4 is the maximum joint angle φ1 when the vehicle is traveling at a constant speed in a straight line, roller 4 does not come into contact with ceiling surface 13. When the pitching angle of roller 4 is the maximum joint angle φ2 when the vehicle is accelerating or decelerating in a straight line, roller 4 comes into contact with ceiling surface 13. When the pitching angle of roller 4 is changing in the increasing direction, roller 4 comes into contact with ceiling surface 13 when the pitching angle of roller 4 is in the range greater than φ1 and equal to or less than φ2.

[0036] The second predetermined pitching angle θp2 is set to an angle larger than the maximum joint angle φ2 during acceleration / deceleration when the vehicle is traveling straight, and equal to or smaller than the maximum joint angle φ3 during maximum steering. In this case, the second predetermined pitching angle θp2 is naturally set to an angle larger than the maximum joint angle φ1 during constant speed traveling when the vehicle is traveling straight.

[0037] In this case, when the pitching angle of roller 4 is the maximum joint angle φ1 when the vehicle is traveling at a constant speed in a straight line, roller 4 does not come into contact with ceiling surface 13. Furthermore, when the pitching angle of roller 4 is the maximum joint angle φ2 when the vehicle is accelerating or decelerating in a straight line, roller 4 does not come into contact with ceiling surface 13. When the pitching angle of roller 4 is the maximum joint angle φ3 when the vehicle is turning at maximum speed, roller 4 comes into contact with ceiling surface 13. When the pitching angle of roller 4 is changing in the increasing direction, roller 4 comes into contact with ceiling surface 13 when the pitching angle of roller 4 is in the range of greater than φ2 and less than or equal to φ3.

[0038] Furthermore, since the predetermined rolling angles θr11, θr12 correspond to the predetermined pitching angle θp2, one of the following two can be applied, similar to the predetermined pitching angle θp2. The first predetermined rolling angles θr11, θr12 are set to angles that are larger than the maximum rolling angle φ11 when the vehicle is traveling straight and at a constant speed, and are equal to or smaller than the maximum rolling angle φ12 when the vehicle is accelerating or decelerating while traveling straight. In this case, the first predetermined rolling angles θr11, θr12 are naturally smaller than the maximum rolling angle φ13 when the vehicle is being steered to the maximum.

[0039] In this case, when the rolling angle of the roller 4 is the maximum rolling angle φ11 when the vehicle is traveling at a constant speed in a straight line, the roller 4 does not come into contact with the ceiling surface 13. When the rolling angle of the roller 4 is the maximum rolling angle φ12 when the vehicle is accelerating or decelerating in a straight line, the roller 4 comes into contact with the ceiling surface 13. When the rolling angle of the roller 4 is changing in the increasing direction, the roller 4 comes into contact with the ceiling surface 13 when the rolling angle of the roller 4 is in the range greater than φ11 and equal to or less than φ12.

[0040] The second predetermined rolling angles θr11, θr12 are set to angles that are larger than the maximum rolling angle φ12 during acceleration / deceleration of the vehicle traveling straight and are equal to or smaller than the maximum rolling angle φ13 during maximum steering. In this case, the second predetermined rolling angles θr11, θr12 are naturally larger than the maximum rolling angle φ11 during constant speed traveling of the vehicle traveling straight.

[0041] In this case, when the rolling angle of the roller 4 is the maximum rolling angle φ11 when the vehicle is traveling at a constant speed in a straight line, the roller 4 does not come into contact with the ceiling surface 13. Furthermore, when the pitching angle of the roller 4 is the maximum rolling angle φ12 when the vehicle is accelerating or decelerating in a straight line, the roller 4 does not come into contact with the ceiling surface 13. When the rolling angle of the roller 4 is the maximum rolling angle φ13 when the vehicle is turned at maximum speed, the roller 4 comes into contact with the ceiling surface 13. When the rolling angle of the roller 4 is changing in the increasing direction, the roller 4 comes into contact with the ceiling surface 13 when the rolling angle of the roller 4 is in the range of greater than φ12 and equal to or less than φ13.

[0042] Here, when the roller 4 is not in contact with the ceiling surface 13, a gap exists between the roller 4 and the ceiling surface 13. Therefore, the larger the pitch angle range in which the roller 4 is not in contact with the ceiling surface 13, the more effectively the roller 4 can suppress the generation of a forcing force in a range up to a large pitch angle. Similarly, the larger the roll angle range in which the roller 4 is not in contact with the ceiling surface 13, the more effectively the roller 4 can suppress the generation of a forcing force in a range up to a large roll angle.

[0043] On the other hand, the larger the pitching angle at which the rollers 4 do not contact the ceiling surface 13, the larger the outer ring 2. Similarly, the larger the rolling angle at which the rollers 4 do not contact the ceiling surface 13, the larger the outer ring 2. Therefore, by not making too large the range of the pitching angle and rolling angle at which the rollers 4 do not contact the ceiling surface 13, and by minimizing the range in which the generation of the forcing force can be suppressed, the effects of miniaturization and suppression of the forcing force can be achieved.

[0044] 4. Details of the orthogonal cross-sectional shape of the groove on the ceiling surface 13 The groove orthogonal cross-sectional shape of the ceiling surface 13 will be described in detail with reference to Figures 9 to 11. As shown in Figure 9, when the roller 4 pitches by a predetermined pitching angle θp2, the contour line OL1, obtained by projecting the roller end surface 32 in the axial direction of the outer ring 2, has the shape shown by the thick solid line. At this time, the roller 4 is not rolling. In this embodiment, one part of the contour line OL1 is defined by the boundary between the circular flat portion 32a and the chamfered portion 32b, and another part of the contour line OL1 is defined by the boundary between the chamfered portion 32b and the roller outer peripheral surface 31. A point on the contour line OL1 that is located on the central axis Lr of the roller 4 and farther from the central axis Lo of the outer ring 2 is defined as the central highest point P1.

[0045] As shown in Figure 10, when the joint angle is 0° and the roller 4 rolls in the forward direction by a predetermined rolling angle θr11, the contour line OL2 of the roller 4 projected in the axial direction of the outer ring 2 has the shape shown by the thick solid line. Therefore, the contour line OL2 is formed by the roller outer peripheral surface 31, the roller end surface 32, and the roller root surface 33. The boundary point of the contour line OL2 between the roller outer peripheral surface 31 and the roller end surface 32 located on the side farther from the central axis Lo of the outer ring 2 is defined as the highest point P2 of the forward rotation edge.

[0046] 11, when the joint angle is 0° and the roller 4 rolls in the reverse direction by a predetermined rolling angle θr12, the contour line OL2 of the roller 4 projected in the axial direction of the outer ring 2 has the shape shown by the thick solid line. Therefore, the contour line OL3 is formed by the roller outer peripheral surface 31, roller end surface 32, and roller root surface 33. The boundary point of the contour line OL3 between the roller outer peripheral surface 31 and roller end surface 32 located on the side farther from the central axis Lo of the outer ring 2 is defined as the highest point P3 of the reverse rotating edge.

[0047] 11, the groove orthogonal cross-sectional shape of the top surface 13 is formed by a line passing through the center highest point P1, the forward rotation edge highest point P2, and the reverse rotation edge highest point P3. Specifically, the groove orthogonal cross-sectional shape of the top surface 13 is formed by a curved shape 13a connecting the center highest point P1 and the forward rotation edge highest point P2, and a curved shape 13b connecting the center highest point P1 and the reverse rotation edge highest point P3. The curved shapes 13a and 13b are preferably formed by an ellipse or a circular arc.

[0048] 5.Effects In the tripod-type constant velocity universal joint 1 of this embodiment, the groove orthogonal cross-sectional shape of the ceiling surface 13 of the raceway groove 10 of the outer ring 2 is formed by a line shape passing through the center highest point P1, the forward rotating edge highest point P2, and the reverse rotating edge highest point P3. The center highest point P1 is a point obtained from the contour line OL1 of the roller end surface 32 when the roller 4 pitches by a predetermined pitching angle θp2. The forward rotating edge highest point P2 is a point obtained from the contour line OL2 of the roller 4 when the roller 4 rotates in the forward direction and rolls by a predetermined rolling angle θr11. The reverse rotating edge highest point P3 is a point obtained from the contour line OL3 of the roller 4 when the roller 4 rotates in the reverse direction and rolls by a predetermined rolling angle θr12.

[0049] Therefore, when the rollers 4 pitch an angle smaller than the predetermined pitch angle θp2, or when they roll an angle smaller than the predetermined roll angles θr11 and θr12, it is possible to prevent the rollers 4 from coming into contact with the ceiling surfaces 13 of the raceway grooves 10 of the outer ring 2. In this way, as long as the pitching and rolling of the rollers 4 is within at least a certain angular range, it is possible to prevent the roller end faces 32 from coming into contact with the ceiling surfaces 13 of the raceway grooves 10 of the outer ring 2, thereby suppressing the generation of a forcing force.

[0050] In particular, the central highest point P1 is defined as a point on the central axis Lr of the roller 4 and located farther from the central axis Lo of the outer ring 2 on a profile line OL1 formed by projecting the roller end face 32 in the axial direction of the outer ring 2 when the roller 4 pitches by the predetermined pitch angle θp2. The positive rotation edge highest point P2 is defined as a boundary point between the roller outer peripheral surface 31 and the roller end face 32 located farther from the central axis Lo of the outer ring 2 on a profile line OL2 formed by projecting the roller 4 in the axial direction of the outer ring 2 when the roller 4 rolls in the forward direction by the predetermined roll angle θr11. The reverse rotation edge highest point P3 is defined as a boundary point between the roller outer peripheral surface 31 and the roller end face 32 located farther from the central axis Lo of the outer ring 2 on a profile line OL3 formed by projecting the roller 4 in the axial direction of the outer ring 2 when the roller 4 rolls in the reverse direction by the predetermined roll angle θr12.

[0051] In this way, the shape of the ceiling surface 13 is defined by considering which position on the groove orthogonal cross-sectional shape of the ceiling surface 13 approaches which point on the roller 4 during pitching and rolling. By configuring in this way, as long as the pitching and rolling of the roller 4 is within at least a certain angular range, the roller end surface 32 can be prevented from contacting the ceiling surface 13 of the raceway groove 10 of the outer ring 2, and the generation of a forcing force can be suppressed.

[0052] (Embodiment 2) The cross-sectional shape of the ceiling surface 13 of the tripod type constant velocity universal joint 1 of the second embodiment will be described with reference to Figures 13 to 17. For ease of explanation, the difference between the opposing distance between the first raceway surface 11 and the second raceway surface 12 and the width of the roller outer circumferential surface 31 is exaggerated in Figures 13 to 17. Therefore, in reality, the difference between the opposing distance between the first raceway surface 11 and the second raceway surface 12 and the width of the roller outer circumferential surface 31 is very small.

[0053] In Figure 13, torque is transmitted between the roller 4 and the first raceway surface 11. When the roller 4 pitches by a predetermined pitch angle θp2, the roller outer peripheral surface 31 contacts the first raceway surface 11, and there is a gap between the roller outer peripheral surface 31 and the second raceway surface 12, the roller end surface 32 is projected in the axial direction of the outer ring 2 to form a contour line OL11 shown by a thick solid line. At this time, the roller 4 is not rolling. In this embodiment, a portion of the contour line OL11 is defined by the boundary line between the circular flat portion 32a and the chamfered portion 32b, and another portion of the contour line OL11 is defined by the boundary line between the chamfered portion 32b and the roller outer peripheral surface 31. A point on the contour line OL11 that is located on the center axis Lr of the roller 4 and farther from the center axis Lo of the outer ring 2 is defined as the first central highest point P11.

[0054] In Figure 14, torque is transmitted between the roller 4 and the second raceway surface 12. When the roller 4 pitches by a predetermined pitch angle θp2, the roller outer peripheral surface 31 contacts the second raceway surface 12, and there is a gap between the roller outer peripheral surface 31 and the first raceway surface 11, the roller end surface 32 is projected in the axial direction of the outer ring 2 to form a contour line OL12 shown by a thick solid line. At this time, the roller 4 is not rolling. In this embodiment, a portion of the contour line OL12 is defined by the boundary line between the circular flat portion 32a and the chamfered portion 32b, and another portion of the contour line OL12 is defined by the boundary line between the chamfered portion 32b and the roller outer peripheral surface 31. A point on the contour line OL12 that is located on the center axis Lr of the roller 4 and farther from the center axis Lo of the outer ring 2 is defined as a second center-highest point P12.

[0055] 15, when the joint angle is 0°, the roller 4 rolls in forward rotation through a predetermined rolling angle θr11, the roller outer peripheral surface 31 contacts the first raceway surface 11, and there is a gap between the roller outer peripheral surface 31 and the second raceway surface 12. The contour line OL13, obtained by projecting the roller 4 in the axial direction of the outer ring 2, has the shape shown by the thick solid line. Therefore, the contour line OL13 is formed by the roller outer peripheral surface 31, the roller end surface 32, and the roller root surface 33. The boundary point of the contour line OL13 between the roller outer peripheral surface 31 and the roller end surface 32, which is located on the side farther from the central axis Lo of the outer ring 2, is defined as the highest point P13 of the forward rotation back surface side edge.

[0056] As shown in Figure 16, when the joint angle is 0°, the roller 4 rolls in the reverse rotation direction by a predetermined rolling angle θr12, the roller outer peripheral surface 31 contacts the second raceway surface 12, and there is a gap between the roller outer peripheral surface 31 and the first raceway surface 11. This results in a contour line OL14 of the roller 4 projected in the axial direction of the outer ring 2, which has the shape shown by the thick solid line. Therefore, the contour line OL14 is formed by the roller outer peripheral surface 31, the roller end surface 32, and the roller root surface 33. The boundary point of the contour line OL14 between the roller outer peripheral surface 31 and the roller end surface 32, which is located on the side farther from the central axis Lo of the outer ring 2, is defined as the highest point P14 of the reverse rotation back surface side edge.

[0057] 17, the groove orthogonal cross-sectional shape of the top surface 13 is formed by a line passing through the first central highest point P11, the second central highest point P12, the forward rotation rear edge highest point P13, and the reverse rotation rear edge highest point P14. Specifically, the groove orthogonal cross-sectional shape of the top surface 13 is formed by a curved shape 113a connecting the first central highest point P11 and the reverse rotation rear edge highest point P14, a curved shape 113b connecting the second central highest point P12 and the forward rotation rear edge highest point P13, and a straight line shape 113c connecting the first central highest point P11 and the second central highest point P12. The curved shapes 113a and 113b may be formed by an ellipse or a circular arc.

[0058] According to this embodiment, when the roller outer peripheral surface 31 is in contact with one of the first raceway surface 11 and the second raceway surface 12 and has a gap with the other, the groove orthogonal cross-sectional shape of the ceiling surface 13 can be set to a shape that takes into account the gap. This allows for reductions in size and weight of the outer ring 2 while taking the gap into account.

[0059] (Embodiment 3) The cross-sectional shape of the ceiling surface 13 of the tripod constant velocity universal joint 1 of the third embodiment will be described with reference to Figures 18 to 20. In the third embodiment, as in the second embodiment, the difference between the opposing distance between the first raceway surface 11 and the second raceway surface 12 and the width of the roller outer circumferential surface 31 is exaggerated in Figures 18 to 20 to facilitate the description.

[0060] 18, when the joint angle is 0°, the roller 4 rolls in the forward direction by a predetermined rolling angle θr11, the roller outer peripheral surface 31 contacts the second raceway surface 12, and there is a gap between the roller outer peripheral surface 31 and the first raceway surface 11. The contour line OL15, obtained by projecting the roller 4 in the axial direction of the outer ring 2, has the shape shown by the thick solid line. Therefore, the contour line OL15 is formed by the roller outer peripheral surface 31, the roller end surface 32, and the roller root surface 33. The boundary point of the contour line OL15 between the roller outer peripheral surface 31 and the roller end surface 32, which is located on the side of the contour line OL15 farther from the central axis Lo of the outer ring 2, is defined as the highest point P15 of the forward rotation transmission side edge.

[0061] 19, when the joint angle is 0°, the roller 4 rolls in the reverse rotation direction by a predetermined rolling angle θr12, the roller outer peripheral surface 31 contacts the first raceway surface 11, and there is a gap between the roller outer peripheral surface 31 and the second raceway surface 12. The outline OL16, projected onto the axial direction of the outer ring 2, has the shape shown by the thick solid line. Therefore, the outline OL16 is formed by the roller outer peripheral surface 31, the roller end surface 32, and the roller root surface 33. The boundary point of the outline OL16 between the roller outer peripheral surface 31 and the roller end surface 32, located on the side farther from the central axis Lo of the outer ring 2, is defined as the highest point P16 of the reverse rotation transmitting side edge.

[0062] As shown in FIG. 20 , the groove orthogonal cross-sectional shape of the top surface 13 is formed by a line passing through the first center highest point P11, the second center highest point P12, the forward rotation transmission side edge highest point P15, and the reverse rotation transmission side edge highest point P16. Specifically, the groove orthogonal cross-sectional shape of the top surface 13 is formed by a curved shape 213a connecting the first center highest point P11 and the reverse rotation transmission side edge highest point P16, a curved shape 213b connecting the second center highest point P12 and the forward rotation transmission side edge highest point P15, and a straight line shape 213c connecting the first center highest point P11 and the second center highest point P12. The curved shapes 213a and 213b may be ellipses or arcs. In this embodiment, the forward rotation rear side edge highest point P13 and the reverse rotation rear side edge highest point P14 are not used.

[0063] The state shown in Fig. 18 can occur when the direction of torque applied to the outer ring 2 and the tripod 3 is reversed in the state shown in Fig. 16. Also, the state shown in Fig. 19 can occur when the direction of torque applied to the outer ring 2 and the tripod 3 is reversed in the state shown in Fig. 17. The groove orthogonal cross-sectional shape of the ceiling surface 13 is set taking such cases into consideration. This allows for the outer ring 2 to be made smaller and lighter in weight, taking the gap into consideration.

[0064] (Embodiment 4) The cross-sectional shape of the ceiling surface 13 of the tripod constant velocity universal joint 1 of the fourth embodiment will be described with reference to Fig. 21. In the fourth embodiment, as in the second and third embodiments, the difference between the opposing distance between the first raceway surface 11 and the second raceway surface 12 and the width of the roller outer circumferential surface 31 is exaggerated in Fig. 21 to facilitate the description.

[0065] As shown in Figure 21, the groove orthogonal cross-sectional shape of the ceiling surface 13 is formed by a line shape passing through the first center highest point P11, the second center highest point P12, the forward rotation back side edge highest point P13, the reverse rotation back side edge highest point P14, the forward rotation transmission side edge highest point P15, and the reverse rotation transmission side edge highest point P16.

[0066] Specifically, the groove orthogonal cross-sectional shape of the top surface 13 is formed by a curved shape 313a connecting the first center highest point P11 and the reverse rotation back side edge highest point P14, a curved shape 313b connecting the second center highest point P12 and the forward rotation back side edge highest point P13, and a linear shape 313c connecting the first center highest point P11 and the second center highest point P12. Furthermore, the groove orthogonal cross-sectional shape of the top surface 13 is formed by a curved shape 313d connecting the forward rotation back side edge highest point P13 and the forward rotation transmission side edge highest point P15, and a curved shape 313e connecting the reverse rotation back side edge highest point P14 and the reverse rotation transmission side edge highest point P16. The curved shapes 313a and 313b may be ellipses or arcs. According to this embodiment, the outer ring 2 can be made smaller and lighter while taking into account the clearance.

Claims

1. an outer ring (2) having a plurality of raceway grooves (10) extending in the axial direction; a tripod (3) having a plurality of tripod shaft portions (22) extending radially outward; a roller (4) fitted onto the tripod shaft portion and rolling in the raceway groove; A tripod-type constant velocity universal joint (1) comprising: The raceway groove includes a first raceway surface (11) constituting one of the groove side surfaces, a second raceway surface (12) constituting the other of the groove side surfaces, and a ceiling surface (13) constituting the groove bottom surface, The roller is a roller outer peripheral surface (31) configured to be able to roll on the first or second raceway surface; a roller end surface (32) facing the ceiling surface among the axial end surfaces of the roller; Equipped with a point on a contour line (OL1, OL11, OL12) obtained by projecting the roller end face in the axial direction of the outer ring when the roller pitches by a predetermined pitching angle (θp2), the point being located on the central axis (Lr) of the roller and farther from the central axis (Lo) of the outer ring, is defined as a central highest point (P1, P11, P12); Among contour lines (OL2, OL13, OL15) obtained by projecting the roller in the axial direction of the outer ring when the roller rolls in a forward rotation direction by a predetermined rolling angle (θr11), boundary points between the outer peripheral surface of the roller and the roller end surface located on the side farther from the central axis of the outer ring are defined as forward rotation edge highest points (P2, P13, P15), Among contour lines (OL3, OL14, OL16) obtained by projecting the roller in the axial direction of the outer ring when the roller has rolled in the reverse rotation direction by a predetermined rolling angle (θr12), boundary points between the outer peripheral surface of the roller and the roller end surface located on the side farther from the central axis of the outer ring are defined as reverse rotation edge highest points (P3, P14, P16), A tripod-type constant velocity universal joint, wherein the groove orthogonal cross-sectional shape of the ceiling surface is formed by a linear shape passing through the center highest point (P1, P11, P12), the positive rotating edge highest point (P2, P13, P15), and the reverse rotating edge highest point (P3, P14, P16).

2. 2. The tripod-type constant velocity universal joint according to claim 1, wherein the groove orthogonal cross-sectional shape of the ceiling surface is formed by a curved shape (13a, 113a, 213a, 313a) connecting the center highest point and the positive rotating edge highest point, and a curved shape (13b, 113b, 213b, 313b) connecting the center highest point and the reverse rotating edge highest point.

3. The central highest point (P11, P12) is a first central highest point (P11) which is a point located on the central axis of the roller and on the far side from the central axis of the outer ring on a contour line (OL11) obtained by projecting the roller end surface in the axial direction of the outer ring when the roller pitches by a predetermined pitch angle, the roller outer peripheral surface contacts the first raceway surface, and there is a gap between the roller outer peripheral surface and the second raceway surface; a second center highest point (P12) which is a point located on the central axis of the roller and on the far side from the central axis of the outer ring on a contour line (OL12) obtained by projecting the roller end surface in the axial direction of the outer ring when the roller pitches by a predetermined pitch angle, the roller outer peripheral surface contacts the second raceway surface, and there is a gap between the roller outer peripheral surface and the first raceway surface; Including, The highest point of the positive rotation edge (P13) is a positive rotation back surface side edge highest point (P13) that is located farther from the central axis of the outer ring and is a boundary point between the roller outer peripheral surface located on the second raceway surface side and the roller end surface of a contour line (OL13) obtained by projecting the roller in the axial direction of the outer ring when the roller rolls in a positive rotation direction by a predetermined rolling angle, the roller outer peripheral surface is in contact with the first raceway surface, and there is a gap between the roller outer peripheral surface and the second raceway surface; The reverse rotating edge highest point (P14) is a reverse-rotation back surface side edge highest point (P14) that is located farther from the central axis of the outer ring and is a boundary point between the roller outer peripheral surface located on the first raceway surface side and the roller end surface on a profile line (OL14) obtained by projecting the roller in the axial direction of the outer ring when the roller rolls in a reverse rotation direction by a predetermined rolling angle, the roller outer peripheral surface is in contact with the second raceway surface, and there is a gap between the roller outer peripheral surface and the first raceway surface; 3. The tripod-type constant velocity universal joint according to claim 1 or 2, wherein the groove orthogonal cross-sectional shape of the ceiling surface is formed by a linear shape passing through the first center highest point (P11), the second center highest point (P12), the forward rotation back side edge highest point (P13), and the reverse rotation back side edge highest point (P14).

4. The groove orthogonal cross-sectional shape of the ceiling surface is A curved shape (113a) connecting the first center highest point and the reverse rotation back side edge highest point; a curved shape (113b) connecting the second center highest point and the positive rotation back side edge highest point; A straight line shape (113c) connecting the first central highest point and the second central highest point; 4. The tripod type constant velocity universal joint according to claim 3, which is formed by

5. The central highest point (P11) is a first central highest point (P11) which is a point located on the central axis of the roller and on the far side from the central axis of the outer ring on a contour line (OL11) obtained by projecting the roller end surface in the axial direction of the outer ring when the roller pitches by a predetermined pitch angle, the roller outer peripheral surface contacts the first raceway surface, and there is a gap between the roller outer peripheral surface and the second raceway surface; a second center highest point (P12) which is a point located on the central axis of the roller and on the far side from the central axis of the outer ring on a contour line (OL12) obtained by projecting the roller end surface in the axial direction of the outer ring when the roller pitches by a predetermined pitch angle, the roller outer peripheral surface contacts the second raceway surface, and there is a gap between the roller outer peripheral surface and the first raceway surface; Including, The highest point of the positive rotation edge (P15) is a positive rotation transmission side edge highest point (P15) that is located farther from the central axis of the outer ring and is a boundary point between the roller outer peripheral surface located on the second raceway surface side and the roller end surface on a profile line (OL15) obtained by projecting the roller in the axial direction of the outer ring when the roller rolls in a positive rotation direction by a predetermined rolling angle, the roller outer peripheral surface is in contact with the second raceway surface, and there is a gap between the roller outer peripheral surface and the first raceway surface; The reverse rotating edge highest point (P16) is a reverse-rotation-transmitting-side edge highest point (P16) that is located farther from the central axis of the outer ring and is a boundary point between the roller outer peripheral surface located on the first raceway surface side and the roller end surface on a profile line (OL16) obtained by projecting the roller in the axial direction of the outer ring when the roller rolls in a reverse rotation direction by a predetermined rolling angle, the roller outer peripheral surface is in contact with the first raceway surface, and there is a gap between the roller outer peripheral surface and the second raceway surface; 3. The tripod-type constant velocity universal joint according to claim 1 or 2, wherein the groove orthogonal cross-sectional shape of the ceiling surface is formed by a linear shape passing through the first center highest point (P11), the second center highest point (P12), the forward rotation transmission side edge highest point (P15), and the reverse rotation transmission side edge highest point (P16).

6. The groove orthogonal cross-sectional shape of the ceiling surface is a curved line shape (213a) connecting the first center highest point and the reverse rotation transmission side edge highest point; a curved line shape (213b) connecting the second center highest point and the positive rotation transmission side edge highest point; A straight line shape (213c) connecting the first central highest point and the second central highest point; 6. The tripod type constant velocity universal joint according to claim 5, which is formed by

7. The highest point of the positive rotation edge (P15) is further a positive rotation transmission side edge highest point (P15) that is located farther from the central axis of the outer ring and is a boundary point between the roller outer peripheral surface located on the second raceway surface side and the roller end surface on a profile line (OL15) obtained by projecting the roller in the axial direction of the outer ring when the roller rolls in a positive rotation direction by a predetermined rolling angle, the roller outer peripheral surface is in contact with the second raceway surface, and there is a gap between the roller outer peripheral surface and the first raceway surface; The reverse rotating edge highest point (P16) is further a reverse-rotation-transmitting-side edge highest point (P16) that is located farther from the central axis of the outer ring and is a boundary point between the roller outer peripheral surface located on the first raceway surface side and the roller end surface on a profile line (OL16) obtained by projecting the roller in the axial direction of the outer ring when the roller rolls in a reverse rotation direction by a predetermined rolling angle, the roller outer peripheral surface is in contact with the first raceway surface, and there is a gap between the roller outer peripheral surface and the second raceway surface; 5. The tripod-type constant velocity universal joint according to claim 3 or 4, wherein the groove orthogonal cross-sectional shape of the ceiling surface is formed by a linear shape passing through the first center highest point (P11), the second center highest point (P12), the forward rotation back side edge highest point (P13), the reverse rotation back side edge highest point (P14), the forward rotation transmission side edge highest point (P15), and the reverse rotation transmission side edge highest point (P16).

8. The groove orthogonal cross-sectional shape of the ceiling surface is A curved shape (313a) connecting the first center highest point and the reverse rotation back side edge highest point; a curved line shape (313b) connecting the second center highest point and the positive rotation back side edge highest point; A straight line shape (313c) connecting the first central highest point and the second central highest point; a line shape (313d) connecting the highest point of the reverse rotation back side edge and the highest point of the reverse rotation transmission side edge; a line shape (313e) connecting the highest point of the positive rotation back side edge and the highest point of the positive rotation transmission side edge; 8. The tripod type constant velocity universal joint according to claim 7, which is formed by

9. the predetermined pitching angle is an angle (φ1) larger than the maximum joint angle of the tripod constant velocity universal joint when the vehicle is traveling straight at a constant speed, 9. The tripod type constant velocity universal joint according to claim 1, wherein the predetermined rolling angle is an angle larger than a maximum rolling angle (φ11) of the roller when the vehicle is traveling straight at a constant speed.

10. a maximum joint angle (φ1) of the tripod constant velocity universal joint when the vehicle is traveling straight at a constant speed is an angle included in the range of 4 to 10 degrees, 10. The tripod-type constant velocity universal joint according to claim 9, wherein a maximum rolling angle (φ11) of said rollers when said vehicle is traveling straight at a constant speed is an angle included in the range of 0 to 5°.

11. the predetermined pitching angle is an angle larger than a maximum joint angle (φ2) of the tripod constant velocity universal joint during acceleration and deceleration of a vehicle traveling straight ahead, 11. The tripod type constant velocity universal joint according to claim 9, wherein the predetermined rolling angle is larger than a maximum rolling angle (φ12) of the rollers when accelerating or decelerating while the vehicle is traveling straight.

12. the predetermined pitching angle is an angle equal to or smaller than a maximum joint angle (φ2) of the tripod constant velocity universal joint when accelerating or decelerating while the vehicle is traveling straight, 11. The tripod type constant velocity universal joint according to claim 9, wherein the predetermined rolling angle is an angle equal to or smaller than a maximum rolling angle (φ12) of the roller when accelerating or decelerating in a straight line of the vehicle.

13. a maximum joint angle (φ2) of the tripod constant velocity universal joint during acceleration and deceleration of the vehicle traveling straight is an angle included in the range of 6 to 20 degrees, 13. The tripod-type constant velocity universal joint according to claim 11, wherein a maximum rolling angle (φ12) of said rollers when accelerating or decelerating in a straight line of said vehicle is an angle included in the range of 0 to 5 degrees.

14. the predetermined pitching angle is an angle smaller than a maximum joint angle (φ3) of the tripod constant velocity universal joint during maximum steering, 14. The tripod type constant velocity universal joint according to claim 1, wherein the predetermined rolling angle is an angle smaller than a maximum rolling angle (φ13) of the roller at the time of maximum steering.

15. a maximum joint angle (φ3) of the tripod constant velocity universal joint during the maximum steering is an angle included in the range of 10 to 25 degrees, 15. The tripod type constant velocity universal joint according to claim 14, wherein a maximum rolling angle (φ13) of said rollers during said maximum steering is an angle included in the range of 0 to 10 degrees.

16. 16. The tripod type constant velocity universal joint according to claim 1, wherein the rollers are fitted onto the tripod shaft portions so as to be tiltable relative to the tripod shaft portions.

Images