JPH02568B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION This invention relates to an improvement in a ball joint in which a socket for swingably holding a ball at the end of a ball stud is molded from plastic. Conventional sockets are made of metal, similar to ball studs, and have a recess at one end with an opening slightly deeper than the radius of the ball and slightly larger in diameter than the equatorial diameter of the ball; An elastic metal ring with a slit open from the slit is fitted by reducing the slit opening and reducing the diameter.Then, the ball of the stud is pushed through the opening, the diameter of the ring is expanded once, and the equator passes over the ring. The ball, and thus the stud, was held in the recess by an elastic metal ring. However, with this method, it is very time-consuming to reduce the diameter of the elastic metal ring and insert it into the recess through the opening, and the holding force to prevent the stud from coming out of the recess is insufficient to open a cut in the recess. The only option was to rely on the spring force of the metal ring.
Since this metal ring is formed by rolling a metal wire, there are variations in ring diameter and cut, and this variation causes a problem in that the holding force is not constant.

Therefore, by molding the socket with plastic, the present invention eliminates the rusting that is a drawback of metal sockets, makes it lighter in weight, makes it easier to incorporate an elastic metal ring, and increases production. While using a metal ring, the opening of the cut in the metal ring in the assembled state is made smaller than in the original state, the holding force of the ball stud does not depend only on the spring force of the metal ring, and the diameter of the ring is reduced.
This improvement was achieved by reducing the size of the incision.

The illustrated embodiment represents a preferred embodiment of a ball joint that achieves the above objects and allows the cap to be attached and removed, and will be described with reference to this embodiment.

Reference numeral 1 designates a ball stud having a ball 2 at its upper end, which is manufactured, for example, from metal. Reference numeral 3 denotes a main body of the socket, which has a ball accommodating portion 4 at one end that is open in the vertical direction, and 5 is a cap that is screwed into the ball accommodating portion 4 from above, and the main body and the cap are each molded from plastic.

The accommodating part 4 has a cylindrical part 6 with a female thread 6' on the inner periphery in the upper half of the interior, and below the cylindrical part 6, a tapered surface 7 whose diameter decreases downward, and a lower end of the tapered surface 7 has a cylindrical part 6 with a female thread 6' on the inner periphery. There is an overhanging step 7', and the bottom of the step is a cylindrical hole 8 that is equal to or slightly larger than the diameter of the equator 2' of the ball 2. The cap 5 also has a male thread 9' on its outer periphery that engages with the female thread 6', and a cylindrical wall 9 whose inner diameter is the same as or slightly larger than the equatorial diameter of the ball.
It has an upper wall 10 that closes the upper end of the cylinder wall and whose outer periphery is a collar 10' extending outward from the cylinder wall 9, and the cylinder wall 9 has an extension part 11 that extends downward beyond the male thread 9'.
The outer surface of the extension part has a tapered surface 11' matching the tapered surface 7 of the receiving part.

The present invention also uses a metal ring 12 made of an elastic metal wire with an open cut 12', but in the present invention, the cap is screwed into the receiving part, and the metal ring 12 is attached to the tapered surface 7 at the lower end of the cap extension 11. By holding it above the small diameter end or step 7' at the lower end, the opening of the incision is made small and the diameter is reduced.

For example, set the diameter of ball 2 at equator 2' to 10 mm.
Then, the metal ring 12 is a metal wire with a diameter of 1 mm, a split width of 3.5 mm, an inner diameter of 9.8 to 10.2 mm, and an outer diameter of
The inner diameter of the cylindrical part 6 of the housing part is 13.1 mm, the inner diameter of the small diameter end of the tapered surface 7 is 10.6 mm, and the cylindrical hole 8 has an inner diameter of 10.0 mm, so step 7' extends 0.3 mm, and the outer diameter of the cap cylinder wall 9 is 13 mm.
mm, the inner diameter of the part that contacts the equator of the ball is
The diameter is slightly expanded downward at a taper angle of about 5 degrees with a diameter of 10 to 10.1 mm, and the lower end of the extension, that is, the tapered surface 1
The outer diameter of the small diameter end of 1' is 11.4 to 11.6 mm.

Therefore, to assemble, insert the ball 2 into the housing part 4 of the main body from below and pass it through the top, then fit the metal ring 12 onto the ball 2 from above and pass the equator 2' down, and then lower the ball stud. , the cap may be screwed into the housing part from above,
A metal ring 12 is inserted into the housing part 4 from above, and then, after screwing the cap a little, a ball is inserted into the housing part from below and the equator passes upward through the metal ring, and then the cap is screwed into the final state.

In any case, the inner diameter of the metal ring is slightly larger or slightly smaller than the equatorial diameter of the ball, so if it is large, there will be no resistance at all, and if it is slightly small, it will cause a slight force to widen the cut in the receiving part. The equator can be passed through a metal ring.
When the cap is completely screwed in, the metal ring is pushed by the lower end of the cap and as it moves downward through the tapered surface 7, the cut 12' is narrowed and the inner diameter becomes smaller than the equator, and the inner diameter of the tapered surface 7' becomes smaller. It is held down at the bottom. Therefore, the holding force that prevents the ball stud from coming out of the socket is different from the conventional one, which simply relies on the spring force of the metal ring, and the cap holds the metal ring against the lower end of the tapered surface 7. Since it depends on the force that reduces the diameter, a desired amount of holding force can be obtained based on the spring force of the ring and the pressing force of the cap.

When cutting the split 12' in the metal ring 12, the two ends 12a and 12b are misaligned as shown in the figure, so when the cap is completely screwed into the housing, the two mismatched ends become the lower end of the cap. The small diameter end face of the lower end of the tapered surface 7 presses the cap upwardly, eliminating looseness between the cap and the main body of the socket.

Also, an object in which the main body of the socket is attached with a screw 3',
A failure may occur between an object to which the ball stud 1 is attached, such as a vehicle body such as an automobile, and a hatchback door that opens and closes an opening in the vehicle body, and it may be necessary to remove the ball joint.

In this embodiment, the cap can be loosened, so if the cap is loosened a little, the metal ring 12 will return to the tapered surface 7 due to its elastic restoring force, without removing the ball stud or socket.
rise and expand its diameter. Therefore, when the ball stud is pulled down, the equator of the ball passes through the metal ring and comes out of the housing, allowing it to be disassembled.
Once the malfunction has been corrected, the ball can be inserted into the housing from below, and then the cap can be screwed in and tightened again.

FIG. 3 shows the case where the cap 5 is slightly loosened, and the ring 12 used has an inner diameter slightly smaller than the equator of the ball. Therefore, the ring is wrapped around the ball just below the equator, but there is an annular gap between the outer periphery of the ring and the inner periphery of the housing section, here between the upper end of the tapered surface 8 or the lower end of the cylindrical section 6. Therefore, even if the inner diameter of the ring is a little smaller than the diameter of the equator, if you pull the ball stud 1 downward, the equator will expand the ring and go down, and the ball stud will come off. Conversely, if you push the ball of the ball stud upward, the equator will expand the ring and pass upward, allowing you to reassemble the cap by screwing it back in. Of course, if the inner diameter of the ring is slightly larger than the equator, the equator will slip through the ring without resistance when the cap is loosened, and the ball stud will come off by itself when disassembled.

As described above, according to the present invention, the extension part of the cap pushes down the metal ring along the tapered surface of the ball accommodating part and reduces the diameter to a predetermined diameter, resulting in errors in manufacturing dimensions of the metal ring (especially when the diameter is larger than the predetermined diameter). The ball stud and socket can be disassembled by loosening or removing the cap as shown in the illustrated embodiment, and the socket can be easily removed during assembly. It is possible to provide a ball joint with no play between the cap and the cap, and no room for noise generation.

The upper part of the interior of the cap 5 may be configured to tightly receive the upper circumference of the ball 2 as in the previous proposal, or to contact the ball 2 in a ring shape above the equator, but as in this embodiment, a plurality of triangular walls 13 may be arranged radially. They may be provided integrally and brought into contact from above.

In addition, in order to prevent the tightened cap 5 from loosening on its own, the cap is provided with a flexible protruding piece 5' having a downward protrusion 14a, and when the cap is completely screwed in, the protrusion 14a is inserted into the hole 14b of the socket body 5. It is preferable that the protrusion 14a and the hole 14b constitute the anti-rotation device 14. To loosen the cap, flip up the protruding piece 5' and remove the protrusion 14.
A is removed from hole 14b. Furthermore, cap 5
It is preferable to provide a tool engaging hole 15 on the top surface of the cap for hooking a crab-shaped tool when screwing in or loosening the cap. Further, instead of the engagement hole 15, a + or - recess may be used to receive the cutting edge of the driver.

The male thread 9' on the outer periphery of the cap and the female thread 6' on the inner periphery of the accommodating portion are preferably multi-thread threads so that the cap can be completely tightened by turning the cap once or twice.

In this embodiment, the cap was removably inserted into the socket by screwing, but a protrusion was provided on one side of the outer periphery of the cap and an inner periphery of the cylindrical part of the housing part, and an L-shaped groove was provided on the other side, and the protrusion was inserted into the L-shaped groove. The cap is pushed into the receiving part by moving it in the longitudinal groove of the L-shaped groove, and then the cap is rotated to move the protrusion into the lateral groove of the L-shaped groove, and when the protrusion reaches the end of the lateral groove, the detent device 1
Alternatively, two annular protrusions may be provided on the outer periphery of the cylinder wall of the cap, the lower protrusion being set to have a slightly smaller diameter than the upper protrusion, while a single annular engagement protrusion may be provided on the inner wall of the accommodating portion. It is also possible to provide a locking groove and temporarily lock the cap by fitting it with the lower protrusion, and after housing the ball, push the cap further and fully lock it by fitting with the upper protrusion.

Furthermore, the cap may be welded into the housing part by high-frequency heating and fixed in a non-removable manner.

[Brief explanation of drawings]

The drawings show one embodiment of the present invention, and FIG. 1 is a vertical sectional view in an assembled state, FIG. 2 is a plan view,
Figure 3 is a longitudinal sectional view with the cap slightly loosened.
Figure 4 is a layout diagram of the disassembled state, and Figure 5 is a plan view of the metal ring. 5 is the cap, 7 is the tapered surface of the accommodating part, 9 is the cylindrical wall of the cap, 11 is its extension, 1
1' is the tapered surface of the extension, 12 is the metal ring, 1
2' indicates the cut, and 12a and 12b indicate the terminals of the ring.

Claims (1)

[Scope of Claims] 1. A ball stud having a ball at its end, a socket main body made of plastic having at its end a vertically penetrating accommodating part into which the ball enters from below, and a socket main body made of plastic having a vertically penetrating accommodating part at the end into which the ball enters from above. It consists of a cap that can be inserted and fixed, and a metal ring whose inner diameter is slightly larger or slightly narrower than the diameter of the equator of the ball and has notches spaced apart, and the receiving part has a lower end that is equal to or equal to the equator of the ball. This also has a slightly larger tapered surface with a diameter reduced downwards, and the cap has a cylindrical wall into which the ball fits inside, and the lower end of the cylindrical wall has a downwardly tapered outer surface with a tapered surface that matches the above-mentioned tapered surface. When the cap is fixed in the housing part, the lower end of the extension part holds the metal ring that has passed down the equator of the ball in the housing part to the lower end of the tapered surface of the housing part, thereby reducing the diameter of the metal ring. A ball joint that resists elasticity and is made smaller than the equator of the ball. 2. The ball joint according to claim 1, wherein both ends of the metal ring facing each other across the cut are staggered.