JPH1144328A - Constant velocity joint - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a mechanism of a low-heating, small and lightweight constant velocity joint by abolishing a cage. SOLUTION: A constant velocity joint 10 is composed of an outer member 20, an inner member 30, rollers 40 and controllers 50. Composite grooves composed of roller track grooves 25 and 33 and controller track grooves 26 and 34 are formed a partial spherical inner peripheral surface 24 of the outer member 20 and a partial spherical outer peripheral surface 32 of the inner member 30 to contact in a spherical surface with each other, and the rollers 40 are housed in the roller track grooves 25 and 33, and the controllers 50 are relatively movably inserted into passing holes 41 of the rollers 40, and both ends of the controllers 50 projecting from the rollers 40 are housed in the controller track grooves 26 and 34, and the roller track grooves 25 and 33 and the controller track grooves 26 and 34 are formed in a wedge shape of turning in the mutually inverse direction, and inversely turning axial tension is made to act on the rollers 40 and the controllers 50, and the roller center is held on a joint plane, and a constant velocity characteristic is secured.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a constant velocity joint used in a power transmission system of an automobile or various industrial machines. More specifically, the invention relates to how a rotating shaft on a driving side and a rotating shaft on a driven side are arranged. The present invention relates to a constant velocity joint of a type that does not slide (plunge) in the axial direction, among constant velocity joints that can always transmit torque smoothly even at a large angle (operating angle).

[0002]

2. Description of the Related Art Drive shafts of automobiles (FIGS. 9 and 1)
Ball joint is the most common type of constant velocity joints used in such applications. As shown in FIGS. 12, 13, and 14, the ball type constant velocity joint (1) includes an outer ring (2), an inner ring (3), a ball (4), and a cage (5). A cage (5) is interposed between the outer ring (2) and the inner ring (3), and the cage (5) is spherical with the inner spherical surface (2a) of the outer ring (2) and the outer spherical surface (3a) of the inner ring (3), respectively. In contact.

[0003] For example, a BJ (ball fixed joint) is composed of an inner spherical surface (2a) of an outer ring (2) and an inner ring (3).
A plurality of arc-shaped track grooves (2b, 3b) are respectively formed on the outer spherical surface (3a) of the outer ring (3a), and the center of curvature (Oo,
Oi) is a joint center (O: the same as the center of curvature of the outer spherical surface (2a) and the inner spherical surface (3a))
Are symmetrical with respect to In other words, the center of curvature (O
o) and the center of curvature (Oi) are equidistant in the opposite direction from the joint center (O) and offset in the axial direction. For this reason, the track formed by the track groove (2b) of the outer ring (2) and the track groove (3b) of the inner ring (3) has a wedge shape that gradually widens from one axial direction to the other. Each ball (4) is housed in this wedge-shaped track and transmits a load between the outer ring (2) and the inner ring (3). A cage (5) is incorporated to hold all the balls (4) in the joint plane (P: plane perpendicular to the bisector of the working angle).

Since the track grooves (2b, 3b) are offset, when the ball (4) transmits a load, an axial force acts on the ball (4). An attempt is made to jump out in the direction in which the grooves (2b, 3b) are opened, that is, in the direction in which the wedge-shaped track space is widened. Accordingly, an axial force acts on the cage (5), and the cage (5) is formed on the inner spherical surface (2a) of the outer ring (2).
And the outer ring (3a) of the inner ring (3).

[0005] The axial force acting on the ball (4) has a characteristic that it increases as the load and the operating angle increase. Therefore,
In order for the joint to operate while transmitting the load, the cage (5) needs to have sufficient strength, and the cage (5) has sufficient strength because it slides while contacting the outer ring (2) and the inner ring (3). It is necessary to have excellent wear resistance and heat resistance.

In order to securely hold the ball (4) on the joint plane (P), the ball (4) is often pressed into the window hole (5a) of the cage (5). (4) exercise. The size of the press fit greatly affects the operability of the joint. In addition, since the ball (4) moves in the window hole (5a) of the cage (5) in the pre-loaded state, heat is generated and the cage (5) is worn.

As described above, the cage (5) has sufficient strength,
Heat resistance and wear resistance are required. In addition, track grooves (2
b, 3b) have an offset, so that the track groove (2, 3b)
The depth of b, 3b) is not uniform in the axial direction. Therefore, when the ball (4) transmits a high load at a shallow depth of the track grooves (2b, 3b), the contact ellipse of the ball (4) increases, and the contact ellipse rides on the shoulder of the track groove where stress is concentrated, Chipping may occur at the shoulder.

As a countermeasure against this, it is conceivable to decrease the surface pressure by increasing the diameter of the ball (4) or the pitch circle diameter. However, there is a disadvantage that the outer diameter of the outer ring (2) increases and the joint becomes larger. Occurs. Also, if the offset amount is reduced, the depth of the track grooves (2b, 3b) naturally becomes more uniform in the axial direction, but there remains a problem that the operability is reduced, which is not an advantageous measure. If the thickness of the cage (5) is reduced, the track grooves (2b, 3b) become deeper, but the strength of the cage (5) decreases. As described above, normally, the thickness of the cage (5) and the depth of the track grooves (2b, 3b) are in a relationship of mutual interaction.

[0009]

As described above, the conventional ball-type constant velocity joint increases the heat generation because the cage (5) is indispensable, and cannot be used at a high normal angle. A great deal of effort is required to manage the dimensions of the window hole of the cage (5) into which the ball (4) enters, and the operability is affected by variations in the dimensions of the cage window hole, which may cause malfunctions and abnormal noise. .

[0010] The high angle strength of the joint is determined by the strength of the cage, which greatly limits the design freedom. Also,
Since it is necessary to ensure the strength of the cage, the depth of the track cannot be made sufficiently large, so that the durability of the joint is reduced, which may cause malfunction.

In addition, a complicated design is required in order to enable the cage to be incorporated, and as a result, the assembling work is also complicated and requires many steps. That is, as shown in FIG. 15, the inner ring (3) and the cage (5) are set, and the cage (5) is rotated by 90 ° with respect to the outer ring (2).
Window hole (5a) of the outer ring (2) track groove (2b)
The outer ring (2) is inserted into the mouth of the outer ring (2) in a state fitted to the land (2c) between them (FIG. 15 (B)), and then rotated by 90 ° to make a spherical contact state (FIG. 15 (C)). Next, the inner ring (3) and the cage (5) are tilted with respect to the outer ring (2), and the ball (4) is pushed into the window hole (5a) of the cage (5) exposed from the end face of the mouth of the outer ring (2). (FIG. 15D).
The assembly is completed when the balls (4) are sequentially inserted into all the window holes (5a). In addition, due to the necessity of assembling the cage (see FIG. 15 (C)), the cavity of the mouth part of the outer ring (2) has to be deep, and the distance between the back face (2d) and the joint center (O) increases. (See FIG. 9B). As a result, not only does the weight of the joint increase, but also when applied to a drive shaft of an automobile, the turning radius of the vehicle may be increased (FIG. 1).
0).

Further, in addition to the cage (5) interposed between the inner and outer rings (3, 2) being in sliding contact with the inner and outer rings (3.2), a window hole (5a) of the cage (5) is provided. Since the ball (4) is press-fitted into the vehicle, the ball is hard to bend by hand, and labor may be required in assembling the vehicle.

As described above, the conventional ball type constant velocity joint requires a cage, and the cage has many problems as described above due to the presence of the cage.

[0014] An object of the present invention is to eliminate the above-mentioned problems. In other words, it is an object of the present invention to provide a small and lightweight constant velocity joint mechanism with low heat generation by eliminating the cage.

[0015]

In order to achieve the above object, a constant velocity joint according to the present invention comprises an outer member, an inner member, a roller, and a controller as main components, and one of the outer member and the inner member is provided. The other side is the driven side. The outer member and the inner member each have a partially spherical inner peripheral surface and a partially spherical outer peripheral surface having the joint center as the center of curvature, and are in sliding contact with the joint center so as to be angularly displaceable in all directions around the joint center.

A plurality of pairs of tracks extending in the axial direction for accommodating the rollers and the controller are formed on the partially spherical inner peripheral surface of the outer member and the partially spherical outer peripheral surface of the inner member. Each pair of tracks is composed of a roller track and a controller track, the roller track is composed of a roller track groove of the outer member and a roller track groove of the inner member, and the controller track is a controller track groove of the outer member and a controller of the inner member. It is composed of track grooves. The controller track groove is arranged at the center of the bottom surface of the roller track groove in parallel with the roller track groove.

The roller is housed in a roller track, and the controller is inserted movably in the axial direction of the roller into a through hole penetrating in the axial direction of the roller at the center of the roller. Housed in a truck. The rollers and the controller are linked in the longitudinal direction of the track, with the controller making a relative movement in the axial direction of the rollers. For example, considering the case where torque is transmitted from the outer member to the inner member, the torque is mainly transmitted through the route of the roller track groove of the outer member → the roller → the roller track groove of the inner member.

The center of curvature of the roller track groove of the outer member and the center of curvature of the roller track groove of the inner member are on axes which are offset from the joint center by the same distance in opposite directions. Therefore, the axial section of the roller track formed by the pair of roller track grooves has a wedge shape in which one of the axial directions is narrow and the other is wide.

The center of curvature of the controller track groove of the outer member and the center of curvature of the controller track groove of the inner member are on an axis equidistant from the joint center in opposite directions. Therefore, the axial section of the controller track formed by the pair of controller track grooves has a wedge shape in which one of the axial directions is narrow and the other is wide.

The opening directions of the wedge shape of the roller track and the wedge shape of the controller track are opposite to each other. Therefore, when the load is transmitted, axial forces opposite to each other act on the roller and the controller. That is, an axial force acts from the narrower to the wider wedge shape of the roller track on the roller, and an axial force acts from the narrower to the wider wedge shape of the controller track on the controller. Therefore, by appropriately setting the offset amount and the like between the roller track and the controller track, it is possible to balance the two axial forces, whereby the roller (roller center) is always held in the joint plane, and so on. A fast fixed joint mechanism is configured. By adopting such a mechanism, the cage for holding the ball in the joint plane in the conventional ball type constant velocity joint can be eliminated.

According to a second aspect of the present invention, the shape of both ends of the controller is a curved surface having a curvature radius equal to the radius of the ball when one ball is applied between the controller track grooves of the outer member and the inner member. It is characterized by. In the joint of the first aspect, if there is a clearance between the groove bottom of the roller track and the roller, the roller is inclined, and the controller is also inclined. When the clearance increases, control by the controller becomes difficult. Therefore, by forming the shape of both ends of the controller to be a curved surface having a curvature radius equal to the radius of the ball when one ball is applied between the controller track grooves of the outer member and the inner member, even if the controller is inclined, Since the clearance between the groove and the groove does not increase, the control function of the controller can be stabilized.

The controller is not limited to a single unit, but may be composed of a plurality of components. The invention of claim 3 is
The controller is constituted by a plurality of cylinders. For example, one controller can be divided into two to form a controller with two cylinders. Since the cylinders (controller components) can move independently of each other, smooth motion can be achieved as a whole controller. Further, as in the invention of claim 4, the controller can be composed of a plurality of balls. By using high-precision steel balls for rolling bearings and the like, labor and time required for processing the controller can be saved, and cost reduction can be realized.

When the controller is composed of a plurality of components, a spacer may be interposed between the controller components. By adjusting the dimensions and number of spacers, a controller with the same component but different axial dimensions can be obtained.
The cost can be reduced by sharing of the data.

According to a sixth aspect of the present invention, the center of curvature of the bottom surfaces of the roller track grooves of the outer member and the inner member is offset similarly to the center of curvature of the roller tracks of the outer member and the inner member. When the clearance between the bottom surface of the roller track groove and the roller increases, the amount of axial movement of the roller increases.Therefore, by offsetting the center of curvature of the bottom surface of the roller track groove in the same manner as the center of curvature of the roller track, the operating angle is reduced. It is preferable to reduce the clearance over the entire area.

The invention according to claim 7 is characterized in that the contact between the upper surface and the lower surface of the roller is a line contact. When the upper surface and the lower surface of the roller are part of a spherical surface whose center of curvature is at the center of the roller, the contact of the roller with the bottom surface of the roller track groove makes point contact, and the posture of the roller becomes unstable. Therefore, it is preferable to make the contact between the upper surface and the lower surface of the roller a line contact and stabilize the attitude of the roller.

[0026]

Embodiments of the present invention will be described below in detail with reference to the accompanying drawings.

The constant velocity joint (10) shown in FIG. 1 includes an outer member (20), an inner member (30), and a roller (4).
0) and a controller (50) as main components.

FIG. 1 is a longitudinal sectional view of the constant velocity joint (10) in a state where the operating angle (θ) is set. Outer member (2
0) has a rotation axis (X), and the inner member (30) has a rotation axis (Y). Either the outer member (20) or the inner member (30) is on the driving side, and the other is on the driven side. Here, the operating angle (θ) refers to the outer member (2
The angle defined by the rotation axis (X) of (0) and the rotation axis (Y) of the inner member (30) is meant. Further, when the rotation axis (X) of the outer member (20) and the rotation axis (Y) of the inner member (30) take a certain operating angle (θ) other than 0 °, the two rotation axes (X, Y) are formed. A plane perpendicular to the bisector of the angle (θ) is called a joint plane (P). When the working angle (θ) is taken, if all the rollers (40) are in the joint plane (P), the distances from the roller center to the two rotation axes (X, Y) are equal, and therefore, both the rotation axes ( (X, Y), the transmission of the rotational movement is performed at a constant speed.
The intersection (O) between the joint plane (P) and the rotation axis (X, Y) is called a joint center. In a constant velocity joint that does not perform a plunging motion, the joint center (O) is fixed regardless of the operating angle (θ).

FIG. 2 (A) shows a cross section passing through the center of the roller (40) of the constant velocity joint (10), and FIG. 2 (B) shows a cross section taken along line BB of FIG. 2 (A). FIG. 2B shows that the operating angle (θ) of the constant velocity joint (10) is 0 °, that is, the rotation axis (X) of the outer member (20) and the rotation axis (Y) of the inner member (30) are coaxial. The state at the top is shown.

The outer member (20) comprises a shaft portion (21) and a mouth portion (23), and is connected to the power transmission system at the shaft portion (21). The mouth portion (23) has a cup shape with a partially spherical inner peripheral surface (24).
A back face (22) perpendicular to the rotation axis (X) is formed at a position that forms a boundary between the shaft part (21) and the mouse part (23).

The outer member (20) is provided with roller track grooves (25) at circumferentially equidistant positions (six places are illustrated in the drawing) of the partially spherical inner peripheral surface (24). And a composite groove including a controller track groove (26).

The roller track grooves (25) are parallel to each other and extend in the axial direction of the outer member (20). The roller track groove (25) is formed at a predetermined depth from the inner peripheral surface (24), and the depth gradually changes in the axial direction. That is, in the case of the illustrated example, when viewed in a vertical cross section (FIG. 3), both the center line and the bottom surface (25a) of the roller track groove are located at the center of curvature (OOL) on the rotation axis (X) of the outer member (20). Is an arc with Also, the cross section (FIG. 2)
(A)), the bottom surface (25a) of the roller track groove (25) is an arc having a center of curvature at the joint center (O), and the side wall surface (25b) is a roller (4) to be described later.
This is an arc having a curvature almost equal to or slightly larger than the curvature of the outer peripheral surface (42) of (0). As illustrated in FIG. 2C, the side wall surface (25b) of the roller track groove (25) may have a contact angle with the outer peripheral surface (42) of the roller (40).

A controller track groove (26) is formed at the center of the roller track groove (25) in parallel with the roller track groove (25). The controller track groove (26) is at the bottom (25a) of the roller track groove (25).
To a predetermined depth, and the depth gradually changes in the axial direction. That is, when viewed in a longitudinal section (FIG. 3), the groove bottom of the controller track groove (26) is an arc having a center of curvature (OOC) on the rotation axis (X) of the outer member (20). The cross-sectional shape of the controller track groove (26) is an arc having a curvature substantially equal to or larger than a cross section of an end portion of the controller (50) described later (FIG. 2).
(A)). The cross section of the controller track groove (26) may have a contact angle with the end face of the controller (50) in some cases.

The inner member (30) has a fitting hole (31) for coupling to a power transmission system and a partially spherical outer peripheral surface (3).
2), and comes into contact with the partial spherical inner peripheral surface (24) of the outer member (20) at the partial spherical outer peripheral surface (32). Since the partial spherical inner peripheral surface of the outer member and the partial spherical outer peripheral surface of the inner member are in direct contact with each other, the area of the contacting portion is reduced by half as compared with the conventional case where a cage is interposed. Also, by eliminating the cage, it is possible to reduce the outer diameter of the outer member and / or increase the depth of the roller track groove by an amount corresponding to the thickness of the cage. In any case, the degree of freedom in design is greatly increased.

The inner member (30) is positioned at equal circumferential positions on the partial spherical outer peripheral surface (32) in the outer member (2).
0) and corresponding composite grooves (33, 33).
34). The roller track groove (33) is formed at a predetermined depth from the outer peripheral surface (32) of the inner member (30), and the depth gradually changes in the axial direction. That is, when viewed in a longitudinal section (FIG. 3), the roller track grooves (3
The bottom surface (33a) of 3) is an arc having a center of curvature (OIL) on the rotation axis (Y) of the inner member (30). Here, the center of curvature of the center line of the roller track groove (33) and the center of curvature of the bottom surface (33a) are the same. When viewed in a cross section (FIG. 2 (A)), the bottom surface (33a) of the roller track groove (33) is an arc having the center of curvature at the joint center (O), and the side wall surface (33b) is a roller (described later). (4
This is an arc having a curvature substantially equal to or slightly larger than the curvature of the outer peripheral surface of 0). Similarly to the case of the outer member (20), the side wall surface (33b) of the roller track groove (33) may be formed to have a contact angle with the outer peripheral surface (42) of the roller (40) (FIG. 2 (C)).

The controller track groove (34) is formed at a predetermined depth from the bottom surface (33a) of the roller track groove (33), and the depth gradually changes in the axial direction. That is, when viewed in a longitudinal section (FIG. 3), the groove bottom of the controller track groove (34) is an arc having a center of curvature (OIC) on the rotation axis (Y) of the inner member (30). The cross-sectional shape of the controller track groove (34) is an arc having a curvature substantially equal to or larger than a cross section of an end of the controller (50) described later (FIG. 2A). The cross section of the controller track groove (34) may have a contact angle with the end face of the controller (50) in some cases.

The roller track grooves (25) of the outer member (20) and the roller track grooves (3) of the inner member (30)
3) are paired and each pair of roller track grooves (25, 3)
The roller (40) is accommodated in the roller track formed in 3). The roller (40) has a through hole (41) in the center, and the outer peripheral surface (42) is a spherical surface having a center of curvature on the axis. In other words, the generatrix of the outer peripheral surface (42) of the roller (40) is an arc having a center of curvature on the axis.

The controller (50) is inserted into the through hole (41) of the roller (40) so as to be movable in the axial direction of the roller. The controller (50) penetrates the roller (40) in the axial direction of the roller, and both ends protruding from the roller (40) enter the controller track grooves (26, 34), respectively.

Referring to FIG. 3, the center of curvature of the partially spherical inner peripheral surface (24) of the outer member (20) and the partially spherical outer peripheral surface (32) of the inner member (30) will be described. Each of the centers of curvature coincides with the joint center (O). The center of curvature (OOL) of the roller track groove (25) and the center of curvature (OOC) of the controller track groove (26) of the outer member (20) are axially offset from the joint center (O) in the opposite direction. . The center of curvature (OIL) of the roller track groove (33) and the center of curvature (OIC) of the controller track groove (34) of the inner member (30) are axially oppositely offset from the joint center (O). .

The center of curvature (OOL) of the roller track groove (25) of the outer member (20) and the center of curvature (OIL) of the roller track groove (33) of the inner member (30) are from the joint center (O). It is offset in the opposite direction in the axial direction by the same distance. The center of curvature (OIC) of the controller track groove (34) of the inner member (30) and the center of curvature (OOC) of the controller track groove (26) of the outer member (20) are opposite to the joint center (O). It is axially offset by the same distance.

Both end surfaces of the roller (40), that is, the upper surface (4)
3) and the lower surface (44) may each be part of a spherical surface having a center of curvature on (an extension of) the axis of the roller (40), in which case the roller (40) and the roller track bottom surface ( 25a) is a point contact, and the attitude of the roller (40) becomes unstable. Then, roller (4)
If the contact between the roller track (0) and the roller track bottom surface (25a) can be brought into line contact, it is advantageous in stabilizing the attitude of the roller (40). FIG. 4 shows an example of the countermeasure, in which the lower surface (44) of the roller (40) is attached to the inner member (3).
0) is a concave surface having the same radius of curvature (Ri) as the bottom surface (33a) of the roller track (33). In other words, the lower surface (44) of the roller (40) has a center of curvature at the center of curvature (OIL) of the bottom surface (33a) of the roller track (33), and has the same radius of curvature (R) as the bottom surface (33a).
This is a curved surface having the arc of i) as a generating line. The upper surface (43) of the roller (40) is a convex curved surface having the same radius of curvature (Ro) as the bottom surface (25a) of the roller track (25) of the outer member (20). In other words, the roller (40)
The upper surface (43) of the roller track (25) is
The curved surface has a center of curvature at the center of curvature (OOL) of 5a) and has a generatrix of the same radius of curvature (Ro) as the base surface (25a).

The outer member (20) and the inner member (3
0) roller track (25, 33) bottom surface (25a, 3)
The center of curvature of 3a) is offset similarly to the center of curvature (OOL, OIL) of the roller track (25, 33).
The bottom surface (25a, 33) of the roller track (25, 33)
When the clearance between a) and the roller (40) increases, the amount of axial movement of the roller (40) increases. Therefore, the bottom surface (25a, 25a) of the roller track (25, 33)
It is preferable that the clearance be reduced over the entire operating angle (θ) by offsetting 33a).

The controller (50) can take various modifications as shown in FIGS. FIG. 5 shows the controller (5
The case where the shape of both end surfaces of 0) is a partial spherical surface having a radius of curvature (r) shorter than the entire length of the controller (50) is shown.

FIG. 6 shows the shape of both end faces of the controller (50) by changing the shape of the outer member (20) and the inner member (30).
As shown by a broken line between the controller track grooves (26, 34), when one ball is applied, the curved surface has a curvature radius equal to the radius (R) of the ball. Roller (40) and roller track bottom (25a, 3
3a), the roller (40) is inclined, and the controller (50) is also inclined. When the clearance increases, the control by the controller (50) becomes difficult. Therefore, as shown by the broken line, the shape of both end faces of the controller (50) is changed to the outer member (2).
0) and a curved surface having a radius of curvature equal to the radius (R) of the ball when one ball is applied between the controller tracks (26, 34) of the inner member (30). The clearance can be prevented from increasing even if the vehicle is tilted.

FIG. 7 shows a configuration in which the controller (50) is divided into two parts. In this case, the controller (50)
Is composed of two cylinders (51), and each cylinder (51)
Is a controller component. Since each controller component (51) can move independently of each other, smooth movement is possible. FIG. 8 shows a case where the controller (50) is composed of two balls (52). By using high-precision steel balls for rolling bearings and the like, labor and time required for processing the controller can be saved, and cost reduction can be realized. When the controller is composed of a plurality of elements, a spacer may be interposed between the controller components. By adjusting the dimensions and number of the spacers, controllers having different axial dimensions can be obtained with the same components, so that the cost can be reduced by sharing parts (controller components).

In assembling the constant velocity joint according to the present invention, first, as shown in FIG. 11A, the inner member (30) is connected to the outer member (20) by the roller track groove of the outer member (20). With the (25) and the land (35) between the adjacent roller track grooves (33) of the inner member (30) in the same phase, the inner member is attached to the mouth portion (23) of the outer member (20). (30) is inserted. Subsequently, the inner member (30) is turned with respect to the outer member (20), and the roller tracks (25, 33) and the lands (27, 35) are adjusted to have the same phase. Next, the controller (50) is inserted into the through hole (41) of the roller (40) to form a set.
As shown in (B), with the inner member (30) inclined with respect to the outer member (20), the roller tracks (25,
A roller (40) is inserted into 33) and both ends of the controller (50) protruding from the roller (40) are inserted into the controller tracks (26, 34). At this time, the degree of tilting the inner member (30) may be slightly larger than the maximum operation angle (see FIG. 1).

FIG. 9 shows a drive shaft unit (A) using a constant velocity joint according to the present invention in comparison with a drive shaft unit (B) using a conventional constant velocity joint. As can be seen from the figure, in the constant velocity joint of the present invention in which the cage is eliminated, it is not necessary to incorporate the cage into the outer ring during assembly (see FIG. 15C), and accordingly, the mouse portion (23) Is also shallow. As a result, the conventional constant velocity joint (FIG. 9)
(B)) Back face (2d) of outer ring (2)
The distance from the back face (22) of the outer member (20) to the joint center (O) in the constant velocity joint (FIG. 9A) according to the present invention is shorter than the distance from the joint center (O) to the joint center (O). You.

The shortening of the distance between the back face and the joint center has the advantage of reducing the size and weight of the joint and, when applied to the drive shaft of a front wheel drive vehicle, makes it easier to align the joint center with the position of the kingpin center. Therefore, it also has the advantage that the minimum turning radius of the vehicle can be reduced. As shown in FIG. 10, it is desirable that the joint center coincides with the position of the kingpin center. However, when the distance between the back face and the joint center increases (FIG. 9B), the joint center coincides with the position of the kingpin center. Is difficult, and as a result, the turning radius of the vehicle must be increased accordingly.

FIGS. 16 and 17 show an embodiment of a constant velocity joint unitized with an axle bearing. In FIG. 16, the outer member (20) of the constant velocity joint (10) is connected to the inner ring (61) of the axle bearing (60) at its shaft (21). The axle bearing (60) includes an inner ring (61) having a flange (62) for attaching a wheel and an outer ring (6) having a flange (64) for attaching to a vehicle body.
5) and a double row of rolling elements (66) interposed between the inner and outer rings. One of the inner races for the double row rolling elements (66) is formed on the inner race (61), and the other is formed on the annular member (63) fitted with the inner race (61). . End faces of the inner ring (61) and the annular member (63) are in contact with the back face (22) of the outer member (20) of the constant velocity joint (10). An electromagnetic pickup (67) and a pulsar ring (68: hatched portion) constituting a wheel speed sensor for an ABS (anti-lock brake system) are attached to the outer ring (62) and the annular member (66), respectively. Pulsar ring for ABS (6
In the case of the type using 8), since the joint center and the kingpin center must be matched, the space for mounting the pulsar ring (68) is sufficient for the constant velocity joint (1).
Although there is a demand for shortening the axial length 0), as described with reference to FIG. 9, since the distance between the back face and the joint center is shortened, such a demand can be satisfied without difficulty. FIG. 17 illustrates a configuration in which the outer member (20 ′) of the constant velocity joint (10) and the inner ring (61 ′) of the axle bearing (60) are integrated.

[0050]

As described above, the present invention eliminates the cage, which has been indispensable in the conventional ball type constant velocity joint, to thereby solve various problems caused by the existence of the cage. To achieve the following remarkable effects.

That is, since the cage is not interposed between the outer member and the inner member, the friction region causing heat generation is greatly reduced. Also, as a result of the friction part in the joint being greatly reduced, the roller can be oriented in the joint plane with a smaller force than in the case where the ball is oriented in the joint plane in the conventional cage. This means that the degree of the wedge for applying the axial force to the roller may be small, and therefore the track offset amount can be reduced. When the offset amount of the track decreases, the unevenness of the track depth in the axial direction is reduced, and particularly, the track depth on the outer side of the mouth portion of the outer member increases. The problem of swelling up on the shoulder of the truck when riding up was also eliminated, and the durability of the joint was greatly improved.

Therefore, the constant velocity joint of the present invention can be used at a high common angle, and when applied to a power transmission system of an automobile, contributes to a great improvement in the degree of freedom in vehicle design. Further, the constant velocity joint of the present invention can greatly reduce the outer diameter of the outer member due to the elimination of the cage.
Enables a design that meets the demand for weight reduction.

Since the constant velocity joint of the present invention does not require a cage, the distance between the back face and the joint center can be greatly reduced as compared with a conventional ball type constant velocity joint which requires a cage. . Therefore, when applied to the drive shaft of a front wheel drive vehicle, the joint center can be easily aligned with the position of the kingpin center when applied to the drive shaft of a front wheel drive vehicle, thereby enabling the reduction of the vehicle turning radius and the height of the vehicle. Greatly contributes to added value.

Furthermore, the complicated assembly process due to the elimination of the cage is greatly reduced, and the workability is greatly improved. Since the cage is not interposed between the outer member and the inner member and the friction is reduced, the operability is greatly improved, and the bending of the joint can be done with less resistance,
In addition to facilitating the work of assembling the vehicle, the vibration transmitted from the engine to the suspension via the joint is also reduced, and the NVH of the vehicle is greatly improved.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a constant velocity joint.

2A is a cross-sectional view, FIG. 2B is a BB cross-sectional view of FIG. 2A, and FIG. 2C is a cross-sectional view showing a modified example of a roller track groove.

FIG. 3 is a schematic longitudinal sectional view of a constant velocity joint.

FIG. 4 is a longitudinal sectional view of a roller.

FIG. 5 is a schematic diagram showing one embodiment of a controller.

FIG. 6 is a schematic diagram showing another embodiment of the controller.

FIG. 7 is a schematic diagram showing another embodiment of the controller.

FIG. 8 is a schematic diagram showing another embodiment of the controller.

9A is a longitudinal sectional view of a product of the present invention, and FIG. 9B is a longitudinal sectional view of a conventional product.

FIG. 10 is an explanatory view showing a drive shaft of an automobile.

FIG. 11 is a process chart showing an assembling process.

FIG. 12 is a cross-sectional view showing a conventional technique.

FIG. 13 is a longitudinal sectional view of the joint of FIG.

FIG. 14 is an enlarged schematic view of FIG. 13;

FIG. 15 is a process chart showing a process of assembling a conventional joint.

FIG. 16 is a longitudinal sectional view showing an embodiment in which a constant velocity joint and an axle bearing are unitized.

FIG. 17 is a longitudinal sectional view showing an embodiment in which a constant velocity joint and an axle bearing are unitized.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Constant velocity joint O Joint center P Joint plane 20 Outer member X Rotating shaft 21 Shaft part 22 Back face 23 Mouse part 24 Inner peripheral surface 25 Roller track groove 25a Bottom surface OOL Center of curvature 25b Side wall surface 26 Controller track groove OOC Center of curvature 30 Inner Member Y Rotation axis 31 Through hole 32 Outer surface 33 Roller track groove 33a Bottom surface OIL Curvature center 33b Side wall surface 34 Controller track groove OIC Center of curvature 40 Roller 41 Through hole 42 Outer surface 43 Upper surface 44 Lower surface 50 Controller 51 Cylinder (controller component) ) 52 ball (controller component) 60 axle bearing

Claims (7)

[Claims] 1. A constant velocity joint having the following (a), (b), (c), and (d). (A) Outer member ・ Equipped with a partially spherical inner peripheral surface having the center of curvature at the joint center. A roller track groove extending in the axial direction at a predetermined depth from the inner peripheral surface is provided at a circumferentially equal position on the inner peripheral surface. A controller track groove extending in the axial direction at a predetermined depth from the bottom surface of the roller track groove; When viewed in a longitudinal section, the center of curvature of the roller track groove and the center of curvature of the controller track groove are offset from the joint center in opposite directions in the axial direction. (B) Inner member ・ Equipped with a partially spherical outer peripheral surface whose center of curvature is the joint center. A roller track groove extending in the axial direction at a predetermined depth from the outer peripheral surface is provided at circumferentially equidistant positions on the outer peripheral surface. A controller track groove extending in the axial direction at a predetermined depth from the bottom surface of the roller track groove; When viewed in a longitudinal section, the center of curvature of the roller track groove and the center of curvature of the controller track groove are offset from the joint center in opposite directions in the axial direction. The center of curvature of the roller track groove of the outer member and the center of curvature of the roller track groove of the inner member are oppositely offset from the joint center by the same distance. The center of curvature of the controller track groove of the outer member and the center of curvature of the controller track groove of the inner member are oppositely offset from the joint center by the same distance. (C) The rollers are housed in roller tracks formed by roller track grooves of an outer member and roller track grooves of an inner member that form a pair. (D) Controller The roller is inserted movably in the axial direction of the roller into a hole passing through the roller in the axial direction of the roller, and both ends are accommodated in controller track grooves of the outer member and the inner member. 2. The controller according to claim 1, wherein both ends of the controller are curved surfaces having a radius of curvature equal to the radius of the ball when one ball is applied between the controller track grooves of the outer member and the inner member. Item 1. Constant velocity joint according to item 1. 3. The constant velocity joint according to claim 1, wherein the controller comprises a plurality of cylindrical bodies. 4. The constant velocity joint according to claim 1, wherein the controller comprises a plurality of balls. 5. The constant velocity joint according to claim 3, wherein a spacer is interposed between the controller components. 6. The roller member according to claim 1, wherein the center of curvature of the roller track groove bottom surface of the outer member and the inner member is offset similarly to the center of curvature of the roller track.
2, 3, 4 or 5 constant velocity joints. 7. The constant velocity joint according to claim 6, wherein the contact between the upper surface and the lower surface of the roller is in linear contact.