Joints and connections – Articulated members – Pivoted
Reexamination Certificate
1999-04-16
2001-02-20
Kim, Harry C. (Department: 3629)
Joints and connections
Articulated members
Pivoted
C403S140000
Reexamination Certificate
active
06190080
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a ball joint device for use in a joint of steering or suspension systems of automobiles, and more particularly to a ball joint of automobiles which removes the damage caused by twist occurring in the assembly process.
2. Description of Related Art
Various types of ball joints for use in a vehicle are well known in the art. A ball joint rotatably and tiltable on any plane surface is generally used for a steering or a suspension system of automobiles. A conventional ball joint has a structure in which a spherical head of a ball stud is inserted into the inside of a ball seat under the condition that its rotational and tilt operation is enabled; the ball seat is fixed to a housing and a dust cover is fixed between the cross portion of a housing and a ball seat.
FIGS. 1 and 4
show an existing ball joint disclosed in Japanese Laid-Open Patent No. Hei 1-172610. A ball seat
102
where a spherical head
101
a
of a ball stud
101
movably inserted is installed in a housing
103
. And then a combining plate
102
a
provided at the closed portion of the ball seat
102
is heated to be bent outwardly so that the combining plate
102
a
is hook-combined with the lower portion of the housing
103
. That is, one plate of a dust cover
104
is fixed by a rib
105
at a groove formed between a hook protrusion
102
b
of the ball seat
102
and a step of the housing
103
.
In such a ball joint, the combining plate
102
a
provided at the lower portion of the ball seat
102
is heated and melted to be bent to the outward of the lower portion of the housing
103
, thus being hook-combined.
To prevent the ball seat
102
inserted into the housing
103
from rotating while in operation, a V-shaped fixing groove (not shown) is provided at the step of the housing
103
where the combining plate
102
a
of the ball seat
102
is hook-combined with the housing
103
, and melted by heating. Thus, the rotation of the combining plate
102
a
of the ball seat
102
is prevented.
However, such a ball joint must be additionally provided with the V-shaped fixing groove, and the combining plate
102
a
must be heated during a manufacturing process adding difficulty and cost to the process. The combining strength between the ball seat
102
and the housing
103
is increased when the thickness of the combining plate
102
a
formed on the ball seat
102
is thickened. However, when the combining plate
102
a
is thickened, it is more difficult to melt.
As shown in
FIGS. 2 and 4
, a ball joint in which a housing
103
where a support formed of a metallic material is welded is provided. After the ball seat
102
formed of a plastic material (including the spherical head
101
a
of the ball stud
101
) is inserted into the housing
103
, a covering cap
106
formed of a plastic material is welded to the lower portion of the ball seat
102
by an ultrasonic vibrator. While welding protrusions
106
a
formed on the covering cap
106
are melted and welded, the ball seat
102
is fixed to the housing
103
. Such a ball joint is disclosed in U.S. Pat. No. 5,011,321 to Kidokoro.
However, the method in which that the ball seat
102
is fixed to the housing
103
by welding a covering cap
106
to the ball seat
102
requires additional equipment, and further, requires an apparatus for verifying the welding state. Though the verification apparatus is employed, it is not easy to verify the state of weldment of the covering cap
106
onto the ball seat
102
with accuracy.
FIGS. 3 and 4
, disclose and alternative ball joint. An outwardly bent annular hook protrusion
102
c
is made at the closing portion of a ball seat
102
where a spherical head
101
a
of a ball stud
101
is inserted. An annular hook protrusion
102
c
is hooked and fixed at the lower portion of a housing
103
, and thus the ball seat
102
is fixed to the housing
103
. The diameter of the annular hook protrusion
102
c
formed at the closing portion of the ball seat
102
is formed to be greater than that of the ball seat
102
. Such a ball joint is disclosed in Japanese Utility Laid-Open Patent No. Hei 5-23852.
However, in such a ball joint, the annular hook protrusion
102
c
may become damaged when a ball seat
102
is inserted in a housing
103
, and a combining strength of an annular hook protrusion
102
c
of the ball seat
102
being hooked and fixed to the housing
103
is weak.
That is, the ball seat
102
is generally inserted by using a tool. Accordingly, when the ball seat
102
does not uniformly receive force from the tool for inserting the ball seat
102
into a housing
103
, the ball seat
102
is twisted. Also, when a twisted ball seat
102
is assembled into the housing
103
, an annular hook protrusion
102
c
is easily broken since the diameter of the annular hook protrusion
102
c
is formed to be greater than that of the ball seat
102
. When the ball seat
102
slips out of the housing
103
by a vertical force of a ball stud
101
during operation of the ball joint, the annular hook protrusion
102
c
cannot withstand the force and is damaged.
FIGS. 5 and 6
illustrate another existing ball joint. The first hook protrusion
112
a
and the second hook protrusion
112
b
are formed at the open portion of a ball seat
112
and a dust cover
104
is fixed by a rib at a fixing groove
112
c
formed between the first hook protrusion
112
a
and the second hook protrusion
112
b.
This configuration avoids the likelihood that the dust cover
104
will receive much stress by the operation of a ball joint, such as by shaking and rotating, and makes assembly process automation possible by inserting a ball seat
112
into a housing
113
and fixing it, then fixing a dust cover
104
. Such a ball joint is disclosed in U.S. Pat. No. 5,676,485 to Lee.
In order to solve problems such as when a ball seat
112
turns inside a housing during the operation of a ball joint and the ball seat
112
gets twisted and damaged by a tool when the ball seat
112
is inserted into the housing
113
, the inside of the housing
113
and the outer body of the ball seat
112
have the same polygonal shape and several incised plates are formed at an annular hook sill
112
d
formed on the ball seat
112
.
In addition, to fix a ball seat
112
in a housing
113
and maintain the fixing strength, a cap
114
is placed on an annular hook sill
112
d
formed at the lower closing portion of the ball seat
1122
. However, the ball joint above has the problem that it can't be easily assembled by an automated process because a ball seat
112
must be inserted into a housing
113
with their polygonal angle being conformed.
SUMMARY OF THE INVENTION
Accordingly, it is an object of the present invention to provide an improved ball joint device for use in a vehicle which eliminates the aforementioned problems encountered with conventional ball joint devices.
Another object of the present invention is to provide a ball joint for use in a vehicle which does not experience the damage caused by twist occurring in the assembly process. To realize the above-mentioned objects, a ball joint of an automobile comprises a spherical head of a ball stud inserted inside of a ball seat under the condition that rotational and tilt operation is enabled. The ball seat above is fixed to a housing and a dust cover is fixed to a fixing groove formed on the outer portion of a ball seat by a rib. A ball joint of automobiles installed on an annular hook sill formed at a cap extending from the other side of the ball seat in the length direction, comprises several projecting parts projected in the radial direction and formed in the direction of length inside of the housing. The housing contains a round section and a concave sill formed at the outside of an annular hook sill.
Still another object of the present invention is to provide a ball joint device for use in a vehicle, which is simple in structure, inexpensive to manufacture, durable in use, and refined in appearance.
Other objects and further sc
Birch & Stewart Kolasch & Birch, LLP
Central Corporation
Kim Harry C.
LandOfFree
Ball joint device for use in a vehicle does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Ball joint device for use in a vehicle, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Ball joint device for use in a vehicle will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2599627