JPH0527348U - Constant velocity joint - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a constant velocity joint capable of further improving the strength of the central portion of the column portion of the cage without hindering the operation when the joint angle is taken. [Structure] A built-up portion 47 that bulges radially inward in a chevron shape is provided at the center of a column portion 46 located between adjacent ball holding windows 41 of a cage 4. The built-up portion 47 increases the cross-sectional area of that portion, and improves the strength of the central portion of the column portion 46, which is the weakest portion in terms of strength. Further, since the build-up portion 47 is formed in a mountain shape, it is possible to form a joint angle without interfering with the cage 4 and the inner joint member 2 at the time of slide-out MAX or slide-in MAX.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a constant velocity joint used for a driving force transmitting shaft portion of an automobile or the like, and more specifically, to maintain the constant velocity of the driving shaft and the driven shaft while performing angular displacement of both shafts and relative displacement in the axial direction. The present invention relates to a permissible cross groove type (VL type) constant velocity joint.

[0002]

[Prior Art]

 The VL type constant velocity joint that has been generally known from the past is a plurality of cylindrical ones that are circumferentially separated from each other in the inner circumference and alternately incline to the opposite side in the circumferential direction at equal angles and extend from one end to the other end. An outer joint member having a first guide groove, and a periphery of the outer joint member coaxially arranged inside the outer joint member at a position corresponding to the first guide groove on the outer periphery of the outer joint member. An inner joint member having a plurality of second guide grooves extending from one side end to the other side end by inclining to the opposite side in the same angle, and rollably arranged between the first and second guide grooves. A plurality of balls for transmitting torque and a cage interposed between the inner and outer joint members for holding the balls in a ball holding window are provided.

In this constant velocity joint, when the drive shaft rotates, its rotational torque is transmitted from the outer joint member to the inner joint member via each ball, and the driven shaft rotates at the same speed as the drive shaft. .. When an axial external force or an external force with a varying joint angle acts between the inner and outer joint members, each ball rolls while being guided by the first and second guide grooves while being regulated by the cage. Relative displacement and angular displacement are allowed.

By the way, in the constant velocity joint, the outer peripheral surface of the inner joint member and the inner peripheral surface of the cage are formed into a substantially spherical shape, and a slight gap is formed between them in the radial direction and the axial direction. Is configured. As shown in FIG. 9, the shoulder surfaces 22a on both sides in the axial direction of the inner joint member 2a are in sliding contact with the inner peripheral surface of the cage when the inner and outer joint members slide in the axial direction, and the joint angle Therefore, the inner joint member 2a is formed of a spherical surface having centers of curvature P ₁ and Q ₁ which are offset equidistantly from the center O ₁ on both sides in the axial direction. Further, the central portion surface 23a located between both shoulder portion surfaces 22a is formed by a cylindrical surface having a deep second guide groove in consideration of the assemblability with the cage. That is, when assembling the inner joint member and the cage, as shown in FIGS. 10 to 12, the inner joint member 2a is substantially perpendicular to the cage 4a, and one second guide groove is formed. Since the inner joint member 2a is inserted inside the cage 4a in a state in which 24a faces the opening inner circumferential surface 48a of the cage 4a in a parallel manner, at that time, the inner joint member 2a is opposite to the opening inner circumferential surface 48a. The diameter of the cylindrical surface of the central surface 23a is maximized within the range where the outer peripheral surface of the inner joint member 2 can pass through.

Since the central portion of the pillar portion located between the adjacent ball holding windows of the cage is the weakest portion in terms of strength, the center portion of the inner circumference is improved in order to improve the strength of that portion. The partial surface is formed as a cylindrical surface, and the cross-sectional area of that portion is increased.

[0006]

[Problems to be solved by the device]

 By the way, it is preferable that the second guide groove of the inner joint member has a deep groove because torque is transmitted between the second guide groove and the balls rolling in the second guide groove. In particular, the central portion of the second guide groove is preferably deeper because it is most frequently used. However, in the case of the above-mentioned conventional constant velocity joint, when the diameter of the central portion surface 23a of the inner joint member formed by the cylindrical surface is increased, the inner surface is formed between the central portion surface 23a and the cylindrical surface of the cage inner peripheral surface. There is a problem in setting the joint angle due to the narrowed gap. That is, as shown in FIG. 13, both the inner and outer joint members 2a, 1a are slid outward in the axial direction so that the inner joint member 2a and the cage 4a are in contact with each other (when sliding out MAX), and When the inner and outer joint members 2a, 1a are slid inward in the axial direction and the inner joint member 2a and the cage 4a are in contact with each other at a joint angle B (when sliding in MAX), the inner joint member 2a Since the central portion surface 23a interferes with the cylindrical inner peripheral central portion surface of the cage 4a, the joint angle cannot be taken.

The present invention has been devised in view of the above circumstances, and a problem to be solved by the present invention is to solve the second problem of the inner joint member without impairing the working range of the joint angle and the assembling property with the cage. Another object is to provide a constant velocity joint in which the central portion of the guide groove can be made deeper.

[0008]

[Means for Solving the Problems]

 The constant velocity joint of the present invention is cylindrical and has a plurality of first guide grooves which are circumferentially spaced from each other in the inner periphery thereof and which are alternately inclined at equal angles to the opposite side in the circumferential direction and extend from one side end to the other side end. And an outer joint member, which is coaxially arranged inside the outer joint member, at a position corresponding to the first guide groove on the outer periphery of the outer joint member, and the like on the opposite side in the circumferential direction with respect to each of the first guide grooves. An inner joint member having a plurality of second guide grooves that are inclined at an angle and extend from one end to the other end, and a plurality of inner joint members that are rollably disposed between the first and second guide grooves and that transmit torque. In a constant velocity joint comprising a ball and a cage which holds each ball by a ball holding window and is interposed between the inner and outer joint members, an outer peripheral surface of the inner joint member has an axial direction thereof. Centers of curvature located on opposite sides and offset equidistantly from the center of the inner joint member to both sides in the axial direction A center formed by a pair of shoulder surfaces formed of spherical surfaces and a spherical surface located between the pair of shoulder surfaces and bulging radially outward from the shoulder surfaces or two or more tapered surfaces. It is characterized in that it is configured with a partial surface.

[0009]

[Action]

 In the constant velocity joint of the present invention, the central surface of the outer peripheral surface of the inner joint member is formed of a spherical surface or two or more tapered surfaces that bulge outward in the radial direction from the shoulder surface. As a result, the second guide groove formed in the inner joint member is formed such that the groove depth of the central portion which is most frequently used is deep.

[0010]

【Example】

 Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a sectional view of the constant velocity joint according to the present embodiment taken along the axial direction, and FIG. 2 is an enlarged sectional view in which an essential part of FIG. 1 is enlarged, and an explanatory view showing the outer peripheral surface shape of the inner joint member. Is shown in FIG. 3, and a cross-sectional view showing the main part of the cage is shown in FIG.

As shown in FIG. 1, the constant velocity joint of the present embodiment has an outer joint member 1 having a first guide groove 15 and an outer peripheral surface composed of a pair of shoulder surface 22 and center surface 23. The inner joint member 2 having a second guide groove 24 formed on the outer peripheral surface thereof, a plurality of balls 3 rotatably arranged between the first and second guide grooves 15 and 24, and each ball A main element is a cage 4 which holds the inner and outer joint members 2 and which is interposed between the inner and outer joint members 2.

The outer joint member 1 is a short cylindrical member having an inner peripheral surface 13 formed to have a constant diameter, and the inner peripheral surface 13 has circumferentially spaced and alternately opposite circumferential directions. Six first guide grooves 15 are formed which are inclined equiangularly to the side and extend from one side end to the other side end in the axial direction. One end of a drive shaft (not shown) is coaxially connected and fixed to one end of the outer joint member 1 through a mounting hole 17 penetrating in the axial direction.

The inner joint member 2 is of a cylindrical shape having a through hole 20 in the center thereof and slightly shorter than the outer joint member 1, and is coaxial inside the outer joint member 1 with a distance. It is located in. As shown in FIG. 3, the outer peripheral surface of the inner joint member 2 has curvature centers P and Q which are located on both sides in the axial direction thereof and are equidistantly offset from the center O of the inner joint member 2 to the both sides in the axial direction. A pair of shoulder surfaces 22 formed of spherical surfaces, and a central surface 23 formed of a spherical surface positioned between the shoulder surfaces 22 and bulging radially outward of the shoulder surfaces 22. Has been done. The central surface 23 has a center of curvature on a straight line M that passes through the center O of the inner joint member 2 and is perpendicular to the axis L, and has a radius R that is within the opening on both sides of the cage 4 described later. It is set to be equal to or larger than the circumference radius r. Then, at the position corresponding to the first guide groove 15 on the outer peripheral surface, there are six strips extending from one side end to the other side end, which are inclined equiangularly to the opposite side in the circumferential direction with respect to the first guide groove 15. Two guide grooves 24 are formed. In the inner joint member 2, one end of a driven shaft (not shown) is fitted into the through hole 20 and is coaxially connected and fixed. The width of the central surface 23 in the axial direction is approximately the same as the conventional width, and the outer diameter of the line of intersection where the central surface 23 and the shoulder surface 22 intersect is approximately the same as the conventional one.

The balls 3 are made of steel and have a spherical shape, and one ball 3 is provided between each of the first and second guide grooves 15 and 24 facing each other in a cross shape. Each ball 3 is arranged such that the center of the ball 3 is located on a plane including the joint center (constant bisector). The cage 4 has a cylindrical shape slightly longer than the outer joint member 1 and is interposed between the inner and outer joint members 2 and 1. Six ball holding windows 41 are formed in the cage 4 at equal angular intervals along the circumferential direction, and the balls 3 are held by the ball holding windows 41. The cage 4 has an inner peripheral surface 43 and an outer peripheral surface 45 which are spherical surfaces with the center of the cage 4 as the center of curvature. Then, as shown in FIG. 4, the inner peripheral central surface 47 of the pillar 46 located between the adjacent ball holding windows 41 of the cage 4 is formed of a cylindrical surface, and the cross-sectional area of that portion becomes large. There is. In addition, the opening inner peripheral surfaces 48 at both ends of the cage 4 are each formed by a cylindrical surface having a radius r.

In the constant velocity joint configured as described above, when the inner joint member 2 and the cage 4 are assembled, the inner joint member 2 is substantially perpendicular to the cage 4 as described above. Then, the inner joint member 2 is inserted into the cage 4 in a state where the one second guide groove 24 faces the opening inner peripheral surface 48 of the cage 4 in a parallel manner. At this time, as shown in FIG. 5, the outer peripheral surface of the inner joint member 2 passing on the side opposite to the inner peripheral surface 48 of the opening has a center surface 23 whose center of curvature lies on the straight line M shown in FIG. It has a half-diameter R and a spherical surface whose radius R is the same as or larger than the radius r of the cylindrical surface 48 of the cage 4, so that it can pass through without interfering with the inner peripheral surface 48 of the opening and be assembled. It will not cause any problems.

In the constant velocity joint configured as described above, when the drive shaft rotates, the rotary torque is transmitted from the outer joint member 1 to the inner joint member 2 via each ball 3, and the driven shaft is driven. It rotates at the same speed as the shaft. Further, when an external force in the axial direction or an external force with a changing joint angle is applied between the inner and outer joint members 2 and 1, each ball 3 is restricted by the cage 4 and is guided to the first and second guide grooves 15 and 24. By being guided and rolling, its relative displacement and angular displacement are allowed.

When the inner and outer joint members 2, 1 form a joint angle in the slide-out MAX and slide-in MAX states, as shown in FIG. 6, the center of the outer peripheral surface of the inner joint member 2 is Since the part surface 23 has a center of curvature on the straight line M, and the length of the radius R is the same as or larger than the radius r of the cylindrical surface 48 of the cage 4, the inside surface of the cage 4 is The joint angle can be smoothly obtained without interfering with the circumferential center surface 47. When the inner and outer joint members 2, 1 make a joint angle with the slide center, a gap is formed between the cage 4 and the inner joint member 2, so that interference occurs between them. do not do.

As described above, according to the constant velocity joint of the present embodiment, the central surface 23 of the outer peripheral surface of the inner joint member 2 passes through the center O of the inner joint member 2 and is perpendicular to the axis L. Since the radius of curvature R is upward and the radius R is the same as or larger than the inner circumference half radius r of both side openings of the cage 4, which will be described later, the joint angle is actuated. The groove depth of the most frequently used central portion of the second guide groove 24 formed in the inner joint member 2 can be formed deeper without impairing the range and the assemblability with the cage 4.

Although the central surface 22 of the inner joint member 2 in the above embodiment is formed as a spherical surface, it may be formed by another method within a range that does not impair the working range of the joint angle and the assembling property with the cage. You can also do it. For example, as shown in FIG. 7, the central surface is composed of two tapered surfaces 23c, or as shown in FIG. 8, the central surface is a cylindrical surface 23d and two tapered surfaces 23e formed on both sides thereof. It can be configured with and.

[0020]

[Effect of the device]

 According to the present invention, the outer peripheral surface of the inner joint member is formed as a spherical surface located on both axial sides of the inner joint member and having a center of curvature which is offset equidistantly from the center of the inner joint member on both axial sides. It is composed of a pair of shoulder surfaces and a central surface formed by a spherical surface or two or more tapered surfaces located between the pair of shoulder surfaces and bulging outward in the radial direction from the shoulder surfaces. Therefore, the groove depth of the central portion of the second guide groove formed in the inner joint member, which is most frequently used, is formed deeper without impairing the working range of the joint angle and the ease of assembly with the cage. be able to.

[Brief description of drawings]

FIG. 1 is a sectional view taken along an axial direction of a constant velocity joint according to an embodiment.

FIG. 2 is an enlarged sectional view in which a main part of FIG. 1 is enlarged.

FIG. 3 is an explanatory view showing the outer peripheral shape of the inner joint member according to the embodiment.

FIG. 4 is a cross-sectional view showing a main part of a cage according to an embodiment.

FIG. 5 is an enlarged front view showing an enlarged state of the inner joint member and the cage when assembled according to the embodiment.

FIG. 6 is an explanatory view showing the relationship between the inner joint member and the cage when the joint angle is taken in the constant velocity joint of the embodiment.

FIG. 7 is a sectional view showing a main part of an inner joint member according to a modification.

FIG. 8 is a sectional view showing a main part of an inner joint member according to a modification.

FIG. 9 is an explanatory view showing an outer peripheral shape of a conventional inner joint member.

FIG. 10 is a front view of a conventional inner joint member and a cage when assembled.

FIG. 11 is a side view of a conventional inner joint member and a cage when assembled.

FIG. 12 is an enlarged view of an essential part of FIG.

FIG. 13 is an explanatory view showing a relationship between an inner joint member and a cage when a joint angle is taken in a conventional constant velocity joint.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Outer joint member 2 ... Inner joint member 3 ... Ball 4 ... Cage 15 ... First guide groove 22 ... Shoulder surface 23 ... Central surface 24 ... Second guide groove

Claims (1)

[Scope of utility model registration request] 1. An outer joint having a plurality of first guide grooves which are cylindrical and which are spaced from each other in the circumferential direction in the inner circumference and are alternately inclined at equal angles to the opposite side in the circumferential direction and extend from one end to the other end. The member and the outer joint member are coaxially arranged inside the outer joint member at a position corresponding to the first guide groove on the outer periphery thereof and inclined at an equal angle to the opposite side in the circumferential direction with respect to each of the first guide grooves. An inner joint member having a plurality of second guide grooves extending from one side end to the other side end;
And a plurality of balls rotatably arranged between the second guide grooves and transmitting torque, and a cage which holds each ball by a ball holding window and is interposed between the inner and outer joint members. In the constant velocity joint, the outer peripheral surface of the inner joint member is formed of a spherical surface that is located on both sides in the axial direction and that has a center of curvature that is offset equidistantly from the center of the inner joint member to both sides in the axial direction. It is composed of a pair of shoulder surfaces and a central surface formed between a spherical surface or two or more tapered surfaces located between the pair of shoulder surfaces and bulging radially outward of the shoulder surfaces. A constant velocity joint characterized by being.