JPH0643537Y2 - Ball joint - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention relates to a ball joint, for example, the rotation of a steering wheel of a vehicle is transmitted to a wheel through a tie rod, or a wheel and a traverse link are provided at a wheel rotation center. The present invention relates to a ball joint that connects and.

(Prior Art) As a conventional ball joint, for example, there is one as shown in FIG. In FIG. 4, reference numeral 1 is a ball joint, and the ball joint 1 is a ball joint socket 3 having a socket hole 3a in a concave shape at a tip end connected to a tie rod 2 for transmitting rotation of a steering wheel (not shown) to the wheel. And a ball stud 6 having a ball 5 inserted into the socket hole 3a by being press-fitted
And a bearing 7 made of a synthetic resin such as polyurethane, 6-nylon, 66-nylon, etc., which is compressed and interposed between the ball 5 and the socket hole 3a. The central portion 6a of the ball stud 6 is fixed to a knuckle arm (shown by a chain double-dashed line in the figure) 9,
Transmits the torque force from the steering wheel to the wheels via the knuckle arm 9. Reference numeral 11 is an annular dust cover, and 12 is a fixing ring. The fixing ring 12 is provided inside the open end 3b of the ball joint socket 3 to prevent the ball 5 and the bearing 7 from coming out of the socket hole 3a. Lubricating oil such as grease is sealed between the bearing 7 and the ball 5.

Generally, in assembling the ball joint, the ball 5 at the tip of the ball stud 6 is press-fitted into the socket hole 3a via the bearing 7. For this reason, the bearing 7 is largely compressed in the thickness direction and is inserted into the socket hole 3a so as to have a so-called large press-fitting margin. The outer surface 5a of the ball 5 and the outer surface 7a of the bearing 7 swing and slide. As a result, these outer surfaces 5a and 7a are worn and play is generated between the ball 5 and the socket hole 3a. When the ball joint is used for a short period of time, the ball 5 comes into close contact with the bearing 7 due to the compression reaction force of the bearing 7 and the ball stud 6
Torque force is constantly transmitted between the ball joint socket 3 and the ball joint socket 3.

(Problems to be solved by the invention) However, when the ball joint 1 is used for a long period of time, the outer surface 5a of the ball 5 and the outer surface 7a of the bearing 7 are further greatly worn or the rigidity of the bearing 7 is deteriorated. Then, if a large amount of looseness occurs between the ball 5 and the socket hole 3a, the reaction force of compression of the bearing 7 decreases, and the torque force between the ball stud 6 and the ball joint socket 3 becomes unstable. There is a problem that

In view of the above, the present invention provides a bearing with a plurality of protrusions which are disposed on an outer side portion of the bearing and protrude outward from the outer side portion, and which are curved toward the side in the axial direction of the ball stud with a large deformation amount. And a recess for accommodating the curved projection so as to be substantially flush with the inner wall surface of the socket hole, the inner wall surface of the socket hole being pressed by the projection. The object of the present invention is to provide a ball joint in which the reaction force of the bearing is stabilized and durability performance is significantly improved.

(Means for Solving Problems) A ball joint according to the present invention is a ball joint in which a ball portion of a ball stud is inserted with a bearing interposed in a socket hole formed in a ball joint socket. Provided in the vicinity of the protrusions on the outer side of the bearing, and a plurality of protrusions that are arranged on the outer side of the bearing and project outward from the outer side and are curved with a large amount of deformation toward the axial direction side of the ball stud. And a recess for accommodating the curved projection so as to be substantially flush with the inner wall surface of the socket hole, and the projection presses the inner wall surface of the socket hole.

(Operation) When assembling the ball joint, the ball portion of the ball stud is inserted into the socket hole with the bearing interposed. The ball joint according to the present invention has a bearing,
The bearing is disposed on an outer side portion of the bearing, protrudes outward from the outer side portion, and is curved toward the axial direction side of the ball stud with a large deformation amount, and a protrusion on the outer side portion of the bearing. A concave portion that is provided in the vicinity of the socket and that accommodates the curved protrusion so as to be substantially flush with the inner wall surface of the socket hole, and the protrusion is configured to press the inner wall surface of the socket hole. Therefore, the tip of the protrusion of the bearing comes into contact with the inner wall surface of the socket hole, and the protrusion has a large press-fitting margin into which the ball portion of the ball stud is inserted.
It will be curved in the concave portion side and stored in the concave portion. Then, the ball portion is in a state of being press-fitted so as to compress the bearing in the thickness direction and inserted into the socket hole. Therefore, the bearing is inserted into the socket hole while having two stable reaction forces, that is, the reaction force due to the compression in the thickness direction thereof and the reaction force curved toward the concave portion of the protrusion.

Further, since the protrusion presses the inner wall surface of the socket hole and is curved in the axial direction of the ball stud with a large deformation amount and is housed in the recess, the elastic force of the protrusion becomes relatively small, The operating resistance of the ball joint at the initial stage of use becomes low. Moreover, since the protrusion is curved and accommodated in the recess with a large amount of deformation, the durability of the ball joint is improved when used for a long period of time. Further, since the bearing is inserted into the socket hole so that the protrusion is substantially flush with the inner wall surface of the socket hole, the bearing should be inserted into the socket hole while the protrusion is in close contact with the recess. As a result, the entire outer peripheral portion of the bearing is brought into close contact with the entire socket hole, and the assemblability of the bearing is improved.

Embodiment An embodiment of the present invention will be described below with reference to the drawings.

1 to 3 are views showing an embodiment of the ball joint according to the present invention.

First, the configuration will be described. In FIG. 1, reference numeral 21 is a ball joint, and the ball joint 21 is connected to a tie rod 22 for transmitting the rotation of a steering wheel (not shown) to the wheels, and has a ball-shaped socket hole 23a formed at the tip end thereof. The joint socket 23 and a spherical ball (ball portion) 2 inserted by being press-fitted into the socket hole 23a.
Ball stud 26 with 5 at the tip, polyurethane,
Ball made of synthetic resin such as 6 nylon, 66 nylon 25
And a bearing 27 that is compressed and interposed between the socket and the socket hole 23a. As shown in FIGS. 1 and 2, the bearing 27 is annularly arranged on the outer portion 27b of the bottom portion 27a in the shape of a hemispherical shell, and protrudes outward from the outer portion 27b to the axial side of the ball stud 26. A plurality of protrusions 27c that can be bent toward a large amount toward the front end, and a recess 27d that is provided in the vicinity of the protrusion 27c of the outer portion 27b of the bearing 27 and that can store the curved protrusion 27c. .

As shown in FIG. 3, when the bearing 27 is inserted into the socket hole 23a, the protrusion 27c is curved with a large amount of deformation toward the axial direction side of the ball stud 26, so that the tip end portion 27e is fixed. The inner wall surface 23c of the socket hole 23a is brought into contact with the inner wall surface 23a of the socket hole 23, and the inner wall surface 23a of the socket hole 23 is housed in the recess 27d so as to be flush with the inner wall surface 23a.

The central portion 26a of the ball stud 26 is fixed to a knuckle arm (indicated by a chain double-dashed line in the figure) 29 and transmits torque force from the steering wheel to the wheel. 31
Is a dust cover, and the annular dust cover 31 is fixed to the ball stud 26 and the ball joint socket 23 at the upper and lower ends thereof, respectively, and prevents gravel and dust from entering the socket hole 23a. 32 is a fixed ring, and the fixed ring 32 is arranged in the open end portion 23b of the socket hole 23a of the ball joint socket 23, and the end of the open end portion 23b is provided to prevent the bearing 27 and the ball 25 from coming out of the socket hole 23a. It is fixed by bending and crimping. The ball 25 of the ball stud 26 is inserted through the bearing 27 so as to have a large press fit allowance in consideration of the wear of the bearing 27 during long-term use.
At this time, the tip of the protruding portion 27c is the inner wall surface 23 of the socket hole 23a.
Abutting on c, the protrusion 27c is curved toward the recess 27 side by the pressure input and is housed in the recess 27d. The bearing 27 is inserted so as to be largely compressed in the thickness direction. The socket hole 23a is filled with oil such as grease.

Next, the operation will be described.

When the ball joint 21 is used for a long time,
25 swings in the socket hole 23a, and the outer surface 25a of the ball 25 and the inner surface 27f of the bearing 27 repeat sliding. Then, the outer surface 25a of the ball 25 and the inner surface 2 of the belling 27
The 7f is greatly worn to reduce its thickness, and the bearing 27 deteriorates in rigidity. Then, the reaction force of compression of the bearing 27 decreases. The ball joint according to the present invention is
Since the protrusion 27c is provided on the outer side portion 27b of the bearing 27,
Corresponding to the decrease in the reaction force of the compression of the bearing 27, the recess 27d
The curved tip portion 27e of the protrusion 27c housed inside presses the inner wall surface 23c of the socket hole 23a in order to restore the original protruding state. A reaction force that the protrusion 27c presses the inner wall surface 23c is applied to the bearing 27, and a decrease in the reaction force of compression of the bearing 27 is captured. Therefore, the bearing 27 presses the ball 25 with a stable reaction force for a long period of time. In addition to this, since the protrusion 27c is curved with a large amount of deformation, the ball stud 26
Generates a working torque by transmitting a stable torque force for a long period of time. Further, since the elastic force can be made relatively small by the projection 27c, the ball joint 21 at the initial stage of use
The operating resistance of can be reduced. Further, since the protrusion 27c is formed on the outer side 27b of the bearing 27 made of synthetic resin, the bearing 27 can be manufactured easily and at low cost by using a mold having a predetermined shape. Further, since the bearing 27 is inserted into the socket hole 23a so that the protrusion 27c is substantially flush with the inner wall surface 23c of the socket hole 23a, the bearing 27 can be mounted in a state in which the protrusion 27c is in close contact with the recess 27d. It can be inserted into the socket hole 23a. Therefore, the entire outer peripheral portion 27b of the bearing 27 can be brought into close contact with the inside of the socket hole 23a, and the assembling property of the bearing 27 can be improved. The case where the protrusion 27c of the bearing 27 according to the present invention is annularly arranged on the bottom 27a of the bearing 27 has been described, but the present invention is not limited to this embodiment, and the protrusion 27c is an outer portion of the bearing 27. Any shape may be used as long as it is 27b.

(Effect) According to the present invention, the bearing has a plurality of protrusions arranged on the outer side of the bearing, protruding outward from the outer side, and curved with a large deformation toward the axial direction side of the ball stud. And a recess for accommodating the curved projection so as to be substantially flush with the inner wall surface of the socket hole, the inner wall surface of the socket hole being provided by the projection. Since it is configured to press, the elastic force of the protrusion can be made relatively small,
The operating resistance of the ball joint in the initial stage of use can be reduced. Further, since the protrusion is curved and accommodated in the recess with a large amount of deformation, the reaction force of the bearing can be stabilized and the durability of the ball joint can be improved when used for a long period of time. Furthermore, since the bearing is inserted into the socket hole so that the protrusion is substantially flush with the inner wall surface of the socket hole, the bearing was inserted into the socket hole while the protrusion was in close contact with the recess. This can be brought into a state, and the entire outer peripheral portion of the bearing can be brought into close contact with the inside of the socket hole to improve the assemblability of the bearing.

[Brief description of drawings]

1 to 3 are views showing an embodiment of the ball joint according to the present invention. FIG. 1 is a longitudinal sectional view thereof, FIG. 2 is an enlarged sectional view of an essential part thereof, and FIG. 3 shows its action. It is a figure. FIG. 4 is a vertical sectional view of a conventional ball joint. 21 …… Ball joint, 23 …… Ball joint socket, 23a …… Socket hole, 23c …… Inner wall surface, 25 …… Ball (ball part), 26 …… Ball stud, 27 …… Bearing, 27d …… Outside part , 27c …… projection, 27d …… recess.

Claims (1)

[Scope of utility model registration request] 1. A ball joint in which a ball portion of a ball stud is inserted with a bearing interposed in a socket hole formed in a ball joint socket, wherein the bearing is arranged on an outer side portion of the bearing and the outer side portion. A plurality of protrusions protruding outward from the ball stud and curving with a large amount of deformation toward the axial direction side of the ball stud, and the curved protrusions provided in the vicinity of the protrusions on the outer side of the bearing. And a recessed portion that is housed so as to be substantially on the same plane as, and the protrusion presses the inner wall surface of the socket hole.