JPH07174158A - Universal joint - Google Patents

Abstract

PURPOSE:To provide a universal joint with a fluctuation of torque smaller than that of a hook joint. CONSTITUTION:An angle restricting part (hole 21a) is provided respectively coaxially with input/output shafts 11, 12, to further provide an immobile body 21 having an annular inner race 21c with a crossing point 01 of axes of the input/output shafts 11, 12 serving as the center along a reference surface S of bisecting an angle formed by the input/output shafts 11, 12. A universal joint has an annular connecting holder 22 rotatably fitted in the inner race 21c of the immobile body 21 and balls 23 fitted in the connecting holder 22 and arranged with a 90 deg. space in a rotational direction to rotate with the connecting holder 22. Further, the joint has an engaging part 24a engaged with the input side angle restricting part (hole 21a), and in addition, has an input side yoke 24 integrally connected to an end part of the input shaft 11 by providing an arc-shaped outer race 24b with the crossing point 01 serving as the center and an output side yoke 25 rotationally 90 deg. displaced relating to this yoke 24 and similarly constituted.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a universal joint which is used, for example, in a steering column or a part of a drive shaft of a vehicle, and more particularly, by connecting an input shaft and an output shaft whose axes intersect with each other at a predetermined joint angle. The present invention relates to a universal joint that transmits the rotation of an input shaft to the output shaft.

[0002]

2. Description of the Related Art As a universal joint of this type, there is a known hook joint having a cross spider, an input side yoke, an output side yoke and the like.

[0003]

In the hook joint, when the torque is transmitted, the torque transmitting surface formed by the cross spider causes an angle variation, and when the joint angle is θ, the output torque To with respect to the constant input torque Ti is The maximum value becomes Ti / cos θ and the minimum value becomes Ticos θ, and the output torque To changes periodically at a cycle of 180 degrees according to the rotation angle of the input shaft, and such torque fluctuation may cause a problem. . The torque fluctuation increases as the joint angle increases. The present invention has been made focusing on the above-mentioned problems,
Its purpose is to provide a universal joint having a simple structure and less torque fluctuation than a hook joint.

[0004]

In order to achieve the above-mentioned object, in the invention of claim 1, the universal joint is
Equipped with an angle restriction unit coaxially with the input shaft and output shaft,
And an immovable body having an annular inner race around the intersection of the axis of the input shaft and the axis of the output shaft along a reference plane that bisects the angle formed by the input shaft and the output shaft,
An annular connecting and holding body that is rotatably mounted on the inner race of the immovable body, and two pairs 4 that are mounted on the connecting and holding body and are arranged at intervals of 90 degrees in the rotation direction and rotate together with the connecting and holding body. A spherical body and an engaging portion that engages with the input side angle regulating portion of the immovable body, and the pair of the spherical bodies arranged opposite to each other along the surface including the input shaft with respect to the immovable body of the spherical body. An input side yoke integrally formed with an end portion of the input shaft and having an outer race formed in an arc shape centering on a rotation center and engaging with the spherical body, and an output side angle regulation of the unmoving body An engaging portion that engages the portion,
And an outer race that is formed in an arc shape centering on a rotation center of the spherical body with respect to the immovable body along a surface including the pair of the spherical bodies and the output shaft that are opposed to each other and engages with the spherical body. An output side yoke integrally connected to the end of the output shaft is provided.

Further, in the invention of claim 2, the universal joint is provided with angle restricting portions coaxially with the input shaft and the output shaft, and a standard for dividing an angle formed by the input shaft and the output shaft into two equal parts. An immovable body having an annular inner race symmetrically with respect to a plane, an annular connection holder rotatably assembled on the inner race of the immovable object, and the reference surface attached to the connection holder. Symmetric with respect to the direction of rotation 1
A pair of spheres arranged at the input shaft side, each pair of spheres arranged at an interval of 80 degrees and rotating with the connection holding body, and an engaging portion that engages with the input side angle regulation portion of the unmoving body And an outer race that is formed in an arc shape around the center of rotation of the spherical body with respect to the immovable body along a surface including the input shaft and engages with the spherical body, and is integrally formed at the end of the input shaft. Along with a surface including the pair of the spherical body and the output shaft that are provided on the output shaft side and that include an input side yoke connected to the An output-side yoke that is integrally formed with an end portion of the output shaft and has an outer race that is formed in an arc shape around a rotation center of the sphere with respect to the immovable body and that engages with the sphere. It was configured.

[0006]

In each of the universal joints according to the first and second aspects of the present invention, the unmoving body is engaged with the engaging portion of the input side yoke and the engaging portion of the output side yoke at each angle regulating portion. The joint angle is maintained, and the rotation and torque of the input shaft are transmitted from the input side yoke to both spheres that engage with the outer race of the input side yoke, and then to the connection holding body that holds these spheres. From the output yoke to the input yoke via both balls that engage with the outer race of the output yoke.

In the universal joint according to the first aspect of the present invention, however, the torque transmission surface composed of two to four spheres does not change in angle during torque transmission, and when the joint angle is θ, a constant input force is applied. Output torque To with respect to torque Ti
The maximum value of Ti is Ti, and the minimum value is Ticos ² θ /
2, the output torque To changes periodically at a cycle of 180 degrees according to the rotation angle of the input shaft. By the way, the maximum value Ti is the maximum value Ti / c in the hook joint.
Since the minimum value Ticos ² θ / 2 is smaller than the os θ and the minimum value Ticos ² θ / 2 is larger than the minimum value Ticos θ in the hook joint, the torque fluctuation generated in the universal joint of the present invention is smaller than the torque fluctuation generated in the hook joint.
It is possible to reduce problems caused by torque fluctuation.

The universal joint according to the invention of claim 1
The minimum required four spheres around the immovable body are 9 in the direction of rotation.
The non-moving body is provided with an interval of 0 degrees, and the input shaft side and the output shaft side of the unmoving body are provided with angle restricting portions, respectively, and the input side yoke and the output side yoke are provided with engaging portions that engage with the angle restricting portions. Since it has a configuration, it has a simple structure and can be manufactured at low cost.

On the other hand, in the universal joint according to the second aspect of the present invention, since each member is always arranged in plane symmetry with respect to the reference plane, the universal joint becomes a constant velocity joint, and torque during torque transmission. No fluctuations occur. Further, the universal joint according to the invention of claim 2 is, like the universal joint according to the invention of claim 1, constituted by an immovable body, a connection holder, four spheres, an input side yoke, an output side yoke, and the like. It has a simple structure and can be manufactured at low cost.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of each invention will be described below with reference to the drawings. 1 and 2 show a universal joint according to the invention of claim 1, in which the axis L1 of the input shaft 11 and the output shaft 12 intersect at a predetermined joint angle θ.
The intersection O1 of the axis line L2 of the above coincides with the center of the spherical immovable body 21. The immovable body 21 is provided with angle restriction portions (holes) 21a and 21b coaxially with the input shaft 11 and the output shaft 12, respectively, and extends along a reference plane S that bisects an angle φ formed by the input shaft 11 and the output shaft 12. Has an annular inner race 21c centered on the intersection O1.
An annular connection holder 22 is rotatably mounted on c. The connection holder 22 has support holes 22a at intervals of 90 degrees in the rotation direction, and a sphere 23 is rotatably assembled in each support hole 22a. Each sphere 23 is an inner member of the immovable body 21. It is rotatably engaged with the race 21a.

Further, the input side yoke 24 integrally connected to the end portion of the input shaft 11 has the immovable body 21 as shown in FIG. 1 (the rotation angle of the input shaft 11 is 0 degree). An engagement pin portion 24a that engages with the input side angle regulation portion 21a is provided,
Further, an arc-shaped outer race 24b having an intersection point O1 (which is also the center of rotation of the spherical body 23 with respect to the unmoving body 21) as a center along a surface (a paper surface of FIG. 1) including the pair of spherical bodies 23 and the input shaft 11 which are arranged to face each other. And a pair of spherical bodies 23 are rollably engaged with the outer race 24b. On the other hand, as shown in FIG. 2 (the rotation angle of the input shaft 11 is 90 degrees), the output side yoke 25 integrally connected to the end of the output shaft 12 has the output side angle of the unmoving body 21. An engaging pin portion 25a that engages with the restriction portion 21b is provided,
Further, an arc-shaped outer race 25b centered on the intersection O1 is provided along a surface (a paper surface of FIG. 2) including the pair of spherical bodies 23 and the output shaft 12 which are arranged to face each other, and the outer race 25b has a pair of outer races 25b. The spherical body 23 is rollably engaged.

In the universal joint of the present embodiment constructed as described above, the immovable body 21 has the angle regulating portions 21a and 21b.
Are engaged with the engagement pin portion 24a of the input side yoke 24 and the engagement pin portion 25a of the output side yoke 25, respectively, and the joint angle θ is maintained. 24 to this outer race 24b
After being transmitted to both spheres 23 that engage with each other, they are transmitted to the connection holding body 22 that holds these spheres 23, and further to the connection holding body 22.
Is transmitted to the output side yoke 25 through both spheres 23 engaged with the outer race 25b of the output side yoke 25, and is transmitted to the output shaft 12.

In the universal joint of this embodiment, however, the torque transmission surface composed of the two to four spheres 23 does not change in angle during torque transmission, and the maximum value of the output torque To with respect to the constant input torque Ti. Becomes Ti, and the minimum value becomes Ticos ² θ / 2, and as shown in FIG. 3, the output torque To becomes 18 depending on the rotation angle of the input shaft 11.
It changes periodically with a cycle of 0 degree. By the way, the maximum value Ti is the maximum value Ti / cos θ in the hook joint.
Since it is smaller and the minimum value Ticos ² θ / 2 is larger than the minimum value Ticos θ in the hook joint,
The torque fluctuation (solid line in FIG. 3) that occurs in the universal joint of the present embodiment is smaller than the torque fluctuation (broken line in FIG. 3) that occurs in the hook joint, and it is possible to reduce problems associated with torque fluctuation.

Further, in the universal joint of the present embodiment, the minimum required four spheres 23 are arranged on the inner race 21c of the immovable body 21 at intervals of 90 degrees in the rotation direction, and the immovable body 21 has holes 21a. , 21b are provided and the input side yoke 24 and the output side yoke 25 are provided with engaging pin portions 24a,
Since the structure is provided with 25a, the structure is simple and can be manufactured at low cost.

In the above embodiment, the sphere 23 is rotatably assembled to the connection holder 22, but the sphere 23 may be integrally attached to the connection holder 22. In this case, the connection holder 22 may be rotatably assembled to the inner race 21c of the immovable body 31 without assembling the spherical body 23 to the inner race 21c of the immovable body 31.

FIGS. 4 to 6 show a universal joint according to the invention of claim 2, which is the same as the above-mentioned embodiment, in which the immovable body 210, the connection holding body 220, the four spherical bodies 230 and the input side yoke. 240 and an output side yoke 250.
As shown in detail in FIG. 6, the unmoving body 210 includes an upper member 211 made of resin, a lower member 212 made of resin, and a pair of left and right springs 21 for urging these members in a separating direction.
The lower member 212 is provided with angle restriction portions (holes) 210a and 210b coaxially with the input shaft 110 and the output shaft 120, respectively. Further, the upper and lower members 211 and 212 of the unmoving body 210 have arcuate grooves 211a that form an annular inner race symmetrically with respect to a reference plane S that bisects an angle φ formed by the input shaft 110 and the output shaft 120. 211b and 212a, 212b are provided, and each circular arc groove 211a, 211b and 212a, 2
An annular connection holder 220 is rotatably attached to 12b.

The connecting and holding body 220 is formed by a ring 221 rotatably assembled to an inner race formed by both arcuate grooves 211a and 212a of the immovable body 210, and both arcuate grooves 211b and 212b of the immovable body 210. Ring 22 rotatably attached to the inner race
2 and a pair of links 223 and 224 that integrally connect these rings 221 and 222, and each of the rings 221 and 222 has a pair of spheres 2 on the outer periphery thereof.
30 is integrally fixed. Each pair of spheres 230
Are symmetrical with respect to the reference plane S and are arranged at intervals of 180 degrees in the rotation direction.
It is designed to rotate with respect to zero. Connection holder 22
Since the rings 221 and 222 are engaged with the circular arc grooves of the immovable body 210, the 0 and the sphere 230 are restricted from moving relative to each other in the longitudinal direction.

The input side yoke 240, which is integrally connected to the end of the input shaft 110, is provided with an engaging pin portion 240a that engages with the input side angle regulating portion 210a of the unmoving body 210, and is arranged on the input shaft side. Pair of spherical bodies 230 and input shaft 110
Has a circular arc-shaped outer race 240b centered on the rotation center O2 of the input shaft side sphere 230 with respect to the unmoving body 210 along a plane including (in FIG. 4). The pair of spherical bodies 230 are slidably engaged with each other. On the other hand, the output side yoke 250, which is integrally connected to the end of the output shaft 120, includes an engagement pin portion 250a that engages with the output side angle regulation portion 210b of the unmoving body 210, and is arranged on the output shaft side. A pair of spherical bodies 230 and an outer race 250b having an arc shape centering on the rotation center O3 of the output shaft side spherical body 230 with respect to the unmoving body 210 along a surface including the output shaft 120 (sheet surface of FIG. 4), A pair of spheres 230 on the output shaft side are rotatably engaged with the outer race 250b.

In the universal joints of FIGS. 4 and 5 constructed as described above, the non-moving body 210 has the respective angle regulating portions 210.
a and 210b, the engaging pin portion 24 of the input side yoke 240
0a and the engaging pin portion 250a of the output side yoke 250 are respectively engaged to maintain the joint angle θ, and the rotation and torque of the input shaft 110 are engaged from the input side yoke 240 to the outer race 240b thereof. Connection holder 2 that holds these spheres 230 after being transmitted to both spheres 230
20 and further engages with the outer race 250b of the output side yoke 250 from the connection holder 220.
0 to the output side yoke 250 and the output shaft 120.
Be transmitted to. In addition, the universal joints of FIGS. 4 to 6 mechanically connect two universal joints of FIGS. 1 and 2 so as to face each other, share an unmoving body, and connect a shaft connecting both joints. It corresponds to the one configured as a holder.

However, in the universal joints shown in FIGS. 4 and 5, since each member is always arranged symmetrically with respect to the reference plane S during torque transmission, the universal joint is a constant velocity universal joint. Therefore, no torque fluctuation occurs during torque transmission. Further, this universal joint is also the same as the universal joint shown in FIG. 1 and FIG. 2, the unmoving body 210, the connection holding body 220, the four spherical bodies 230, the input side yoke 240, and the output side yoke 25.
It is composed of 0 etc., its structure is simple and it can be manufactured at low cost.

[Brief description of drawings]

1 is a partially cutaway side view showing an embodiment of a universal joint according to the invention of claim 1 in which a surface including a pair of spheres and an input shaft is represented as a paper surface.

FIG. 2 is a partially cutaway side view when the input shaft is rotated 90 degrees from the state of FIG.

FIG. 3 is a graph showing the relationship between the rotation angle of the input shaft and the output torque in the universal joint shown in FIGS. 1 and 2 and a conventionally known hook joint.

FIG. 4 is a side view showing an embodiment of a universal joint according to the invention of claim 2.

5 is a side view when the input shaft is rotated 90 degrees from the state of FIG.

6 is a side view of the immovable body shown in FIGS. 4 and 5. FIG.

[Explanation of symbols]

11 ... Input shaft, 12 ... Output shaft, θ ... Predetermined joint angle, L1 ... Input shaft axis, L2 ... Output shaft axis, O1 ...
Intersection point, 21 ... Immovable body, 21a ... Input side angle regulating section, 21
b ... Output side angle regulation part, 21c ... Annular inner race, 22 ... Connection holder, 23 ... Sphere, 24 ... Input side yoke, 24a ... Engagement pin part, 24b ... Arc-shaped outer race, 25 ... Output side Yoke 25a ... Engaging pin portion 25
b ... Arc-shaped outer race, 110 ... Input shaft, 120
... Output shaft, θ ... Predetermined joint angle, L1 ... Input shaft axis, L2 ... Output shaft axis, O1 ... Intersection point, O2, O3 ... Rotation center, 210 ... Immovable body, 210a ... Input side angle regulating section, 210b ... output side angle regulation part, 220 ... connection holding body, 230 ... spherical body, 240 ... input side yoke, 240a ...
Engagement pin portion, 240b ... Arc-shaped outer race, 25
0 ... Output side yoke, 250a ... Engaging pin portion, 250b ...
Arc-shaped outer race.

Claims (2)

[Claims] 1. A universal joint that connects an input shaft and an output shaft whose axes intersect with each other at a predetermined joint angle and transmits the rotation of the input shaft to the output shaft, the coaxial joint being coaxial with the input shaft and the output shaft. An annular inner race, each of which is provided with an angle restricting portion, and whose center is an intersection of the axis of the input shaft and the axis of the output shaft along a reference plane that divides the angle between the input shaft and the output shaft into two equal parts. An unmoving body having the same, an annular connecting holder that is rotatably assembled on the inner race of the unmoving object, and an annular connecting holder that is assembled to the connecting holder and is arranged at intervals of 90 degrees in the rotational direction together with the connecting holder. Two to four rotating
A spherical body and an engaging portion that engages with the input side angle regulating portion of the immovable body, and the pair of the spherical bodies arranged opposite to each other along the surface including the input shaft with respect to the immovable body of the spherical body. An input side yoke integrally formed with an end portion of the input shaft and having an outer race formed in an arc shape centering on a rotation center and engaging with the spherical body, and an output side angle regulation of the unmoving body A pair of spheres that are arranged to face each other, and are formed in an arc shape around the center of rotation of the sphere with respect to the unmoving body, along a surface that includes the pair of the spheres and the output shaft that are opposed to each other. A universal joint having an outer race that engages with a sphere, and an output side yoke that is integrally connected to an end of the output shaft. 2. A universal joint which connects an input shaft and an output shaft whose axes intersect with each other at a predetermined joint angle and transmits the rotation of the input shaft to the output shaft, and which is coaxial with the input shaft and the output shaft. An immovable body, each having an angle regulation part, and having an annular inner race symmetrically with respect to a reference plane that bisects the angle formed by the input shaft and the output shaft, and rotatable on the inner race of this immovable body. And a pair of spherical bodies that are assembled to the connection holding body and are arranged symmetrically with respect to the reference plane at 180 ° intervals in the rotation direction and rotate together with the connection holding body. A rotation of the spherical body with respect to the unmoving body along a surface including the pair of spherical bodies arranged on the input shaft side and the input shaft, the engaging portion engaging with the input side angle regulating section of the unmoving body Formed in an arc shape centered on the center An input side yoke having an outer race engaged with the spherical body and integrally connected to an end portion of the input shaft; and an engaging portion engaging with an output side angle regulating portion of the unmoving body. And an outer race that is formed in an arc shape around the rotation center of the spherical body with respect to the immovable body along a surface including the pair of spherical bodies arranged on the output shaft side and the output shaft and engages with the spherical body. A universal joint having an output-side yoke integrally connected to the end of the output shaft.