JPS6235110A - Rod with ball joint - Google Patents

Abstract

PURPOSE:To improve productivity together with light weight and high accuracy by feeding a rod member on the inner surface of a cylindrical race member which is buried in the end part of a rod section consisting of synthetic resin so as to form a sliding resin which retains slidably both an internal cylinder fitting and a race member in a uniform spherical clearance between them. CONSTITUTION:On both end parts of a rod 10 made of resin reinforced by glass fiber having an elliptic sectional form or the like, a ball joint part 23 is formed. Here the ball joint part 23 is composed of an internal cylinder fitting 14, which has a pivot insertion hole 24 and a spherical convex 26 on the outside surface, and a race fitting 16, which has a spherical concave 28 forming a uniform clearance between the spherical convex 26 and itself and a communication hole 30 in a cylindrical wall, and a sliding resin 18, which formed into one with a link part 22 through the communication hole 30. Further the sliding resin 18 adheres to the spherical concave 28 to make it possible to slide on the spherical convex 26.

Description

Detailed Description of the Invention (Technical Field) The present invention relates to a rod in which a ball joint mechanism is incorporated in at least one end, such as a stabilizer link rod or a suspension link rod in an automobile suspension. This relates to a rod with a ball joint made of synthetic resin.

(Conventional technology) An arm used in vehicle suspension.

Links, rods, etc. (hereinafter collectively referred to as rods) have a ball joint mechanism built into one or both of their ends in order to reduce torsional rigidity and prying rigidity. Some are designed to be connected to a vehicle body side member or an axle side member via.

For example, a ball joint mechanism is usually built into one end of a stabilizer link rod in an automobile suspension, and a ball joint mechanism is built into one or both ends of a suspension link rod.

By the way, in the past, in such a rod, the rod and the ball joint were manufactured separately, and the separately manufactured ball joint was fitted into and held by a link formed at the end of the rod. , a ball joint was incorporated into the rod.

(Problems) Therefore, with conventional rods with ball joints, the work of assembling the ball joints into the rods is troublesome, and the manufacturing cost of assembled products in which the rods and ball joints are assembled increases. there were.

On the other hand, in order to reduce the weight of vehicles and improve their corrosion resistance, it is being considered to convert such lofts from conventional ones made of metal to ones made of resin. If such rods are made of resin, not only will it be possible to reduce the weight of the vehicle and improve corrosion resistance, but also the elasticity of the rods can be improved, which can also be expected to suppress vibrations. Since it becomes possible to hold the ball joint at the same time as the rod is formed, it is possible to omit the troublesome work of assembling the ball joint into the rod, and it is also expected to improve the productivity of rods with ball joints. However, if such a rod is simply made of a synthetic resin material, due to its structure, a weld line of synthetic resin will be formed on the link part that holds the ball joint, and the link part that holds the joint will be damaged. There is a problem that the mechanical strength of the material is reduced.

(Solution) Against this background, the present invention has been made to provide a rod with a ball joint made of synthetic resin that is easy to manufacture and has excellent mechanical strength. The gist of this is that in a rod with a ball joint that has a ball joint at at least one end of the rod made of a synthetic resin material, the ball joint is located at (a) an axially intermediate portion; (b) an inner cylinder having a spherical convex surface on its outer circumferential surface and into which a predetermined pivot shaft is inserted; It is positioned on the outside of the inner cylindrical metal fitting to form a uniform gap along the spherical convex surface with the spherical convex surface of the inner cylindrical metal fitting, and is embedded and held in the end of the loft portion on the outer peripheral surface. a cylindrical race member having a through hole opening in the spherical concave surface;
C) The synthetic resin material constituting the rod portion is made to flow into the gap between the spherical concave surface of the race member and the spherical convex surface of the inner cylinder fitting through the through hole of the race member, so that it is integrated with the rod portion. A sliding resin is formed on the inner peripheral surface and slidably holds the spherical convex surface of the inner cylindrical fitting.

(Functions and Effects) According to such a rod with a ball joint, the rod part is made of synthetic resin material, so it is lighter in weight than a conventional metal rod, and it is less susceptible to mechanical damage due to corrosion. There is no reduction in the target strength. Also,
Since it has superior elasticity compared to metal rods, it is advantageous in suppressing vibrations, and it also improves productivity because the ball joint mechanism can be completed at the same time as the rod part is formed. It improves significantly.

Furthermore, in the rod with a ball joint according to the present invention, the sliding resin that slidably holds the inner cylindrical metal fitting of the ball joint portion is formed between the spherical convex surface of the inner cylindrical metal fitting and the spherical concave surface of the race member. In addition to being formed within the uniform gap formed by
Since the synthetic resin material constituting the sliding resin is made to flow through the through hole provided in the spherical concave surface of the race member, the synthetic resin material is uniformly contracted toward the race member, that is, toward the outside in the radial direction. Therefore, a uniform clearance can be obtained between the inner circumferential surface of the sliding resin and the spherical convex surface of the inner cylindrical metal fitting, and a highly accurate ball joint mechanism with no backlash can be obtained. In addition, since such sliding resin can be molded at the same time as the rod part, productivity is further improved compared to simply replacing a metal rod with synthetic resin, which further reduces manufacturing costs. becomes possible.

Furthermore, with such a rod with a ball joint, the weld line that occurs during molding can be formed in the sliding resin inside the race member, which makes the race member easier to use than when the rod is simply made of synthetic resin. This has the advantage that the mechanical strength of the link part to be held can be further improved, and since the lace member is embedded integrally between the link part and the sliding resin, the link part can be reinforced by this lace member. There is also the advantage that it can be done.

(Example) Hereinafter, in order to clarify the present invention more specifically,
Examples thereof will be described in detail based on the drawings.

FIGS. 1 and 2 are a front sectional view and a plan sectional view showing essential parts of a suspension link rod, which is an example of a rod with a ball joint according to the present invention. In those figures, reference numeral 10 denotes a synthetic resin rod having an elliptical cross section, and inner cylinder fittings 14 are attached to both ends of the rod. The race fitting 16 is provided with a ball joint portion 23 consisting of a sliding resin 18 and a link portion 22 (however, only the ball joint portion 23 at one end side is shown in the figure). It is also possible to attach a so-called rubber bushing to the other end (not shown) of the rod portion 10, which is designed to block or attenuate vibrations using a rubber elastic body.

Here, the inner cylindrical metal fitting 14 has a cylindrical shape, and its hollow part is an insertion hole 24 into which a predetermined pivot is inserted and attached, while the outer circumferential surface of its axially central part is a spherical convex surface. It is said to be 26.

On the other hand, the race fitting 16 has a cylindrical shape that is shorter than the inner cylinder fitting 14, and the inner circumferential surface of the axially central portion thereof is
A spherical concave surface 28 having a slightly larger diameter than the spherical convex surface 26 of the inner cylindrical fitting 14 is arranged concentrically at a predetermined distance on the outside of the inner cylindrical fitting 14. A uniform gap is formed along the spherical convex surface 26 between the spherical convex surface 26 and the spherical convex surface 26 . Four through holes 30 are formed at equal intervals in the circumferential direction, passing through the cylindrical wall of the race fitting 16 and opening at the axial center of the spherical concave surface 28.

Further, the link portion 22 is formed integrally with the rod portion 10 so as to surround the outer peripheral surface of the race fitting 16, and the sliding resin 18 is formed on the spherical concave surface 2 of the race fitting 16.
8 and the spherical convex surface 26 of the inner cylinder fitting 14, it is formed integrally with the link part 22 through the through hole 30 of the race fitting 16, and is fixed to the spherical concave surface 28 of the race fitting 16 on the outer peripheral surface. On the other hand, the spherical convex surface 26 of the inner cylinder fitting 14 is slidably held on the inner peripheral surface.

That is, when manufacturing such a rod, as shown in FIGS. 3 and 4, first, the inner cylindrical fitting 14 and the race fitting 16 are formed using predetermined molding molds 32, 34 and 36. , their spherical convex surface 26 and spherical concave surface 28
Hold and set concentrically so that a predetermined gap is formed between the two. Note that here, the spherical concave surface 28 of the race fitting 16 is subjected to an adhesive treatment in advance, if necessary.

In this state, a predetermined synthetic resin material 38 is injected into the forming space of the rod portion 10 through a sprue (not shown). In this way, as shown by the arrows in FIGS. 5 and 6, the synthetic resin material 38 injected into the formation space of the rod portion 10 is transferred from the formation space of the rod portion 10 to the link portion 22. The rod portion 10. Link part 2
2 and the sliding resin 18 are molded at the same time.

In addition, here, the rondo part 10. As the resin material 38 constituting the link part 22 and the sliding resin 18, various resin materials with lubricating properties such as nylon can be used, but from the viewpoint of ensuring the mechanical strength of each part of the rod, Generally fiberglass.

A resin material reinforced with carbon fiber, aromatic polyamide (Kevlar) fiber, etc. is used, and among them, resin such as nylon and a diameter of about 0.2 to 1 μmφ are used.

A resin material with excellent sliding performance, such as one reinforced with fine short fibers such as potassium titanate whiskers having a length of about 5 to 30 μm, can be advantageously used. In other words, if such fiber-reinforced resin with excellent sliding performance is used, it is possible to improve the mechanical strength of the opening and other parts, but the fibers also strengthen the spherical convex surface 26 of the inner cylinder fitting 14.
It is possible to maintain the spherical convex surface 26 with appropriate lubricity while avoiding damage to the spherical convex surface 26, and also to prevent the resin from thinning due to sliding with the spherical convex surface 26. You can also get .

According to such suspension link Rondo, since the rod portion 10 is made of the synthetic resin material 38, it is possible to reduce the weight of the vehicle and improve corrosion resistance.
Since the elasticity is improved, it is also advantageous in suppressing vibrations.

In addition, in the ball joint portion 23, the inner cylindrical metal fitting 14
A sliding resin 18 that slidably holds the inner cylinder fitting 14 is molded within a uniform gap formed between the spherical convex surface 26 of the inner cylinder fitting 14 and the spherical concave surface 28 of the race fitting 16, and the sliding resin 18 Since the synthetic resin material 38 constituting the race fitting 18 flows into the gap through the through hole 30 formed by opening in the spherical concave surface 28 of the race fitting 16, when the synthetic resin material 38 is contracted, the synthetic resin material 38 flows into the radially outer race fitting 16. 16 side, the inner peripheral surface of the sliding resin 18 and the inner cylinder fitting 14
A uniform clearance is obtained between the spherical convex surface 26 and a good spherical sliding movement without backlash. Furthermore, since such sliding resin 18 can be molded at the same time as molding the rod portion 10 and the link portion 22, there is an advantage that productivity is high and manufacturing costs can be significantly reduced.

Further, during the molding, the synthetic resin material 38 is transferred from the forming space of the rod portion 10 to the link portion 22 as described above.
The weld line is guided from the formation space of the link portion 22 to the formation space of the sliding resin 18 through the through hole 30 of the race fitting 16, so that the weld line is connected to the sliding resin inside the race fitting 16. 18 and is avoided from being formed on the link portion 22, which also has the advantage of avoiding reduction in the mechanical strength of the link portion 22 due to the weld line. In addition, a race fitting 16 is provided on the inner peripheral surface of the link portion 22.
Since they are fixed together, this also has the advantage of improving the mechanical strength of the link portion 22.

In addition, in such a rod, a dust boot will be arranged between the respective ends of the inner cylinder metal fitting 14 and the race metal fitting 16, as necessary.

Although the embodiments of the present invention have been described in detail above, these are literal illustrations, and it goes without saying that the present invention should not be construed as being limited by such descriptions.

For example, in the embodiment, the spherical concave surface 2 of the race fitting 16
8 are opened at the center in the axial direction, and four through holes 30 are formed at equal intervals in the circumferential direction, so that the synthetic resin material 38 is guided into the forming space of the sliding resin 18 through the four through holes 30. However, the formation position, number, etc. of the through holes 30 can be changed as appropriate depending on the material of the synthetic resin material, molding conditions, etc.

Further, in the above embodiment, the rod portion 10 had an elliptical cross-sectional shape, but the rod portion 10 may have a circular or rectangular cross-sectional shape.

It is possible to adopt various shapes such as (2) shape and H shape.

Furthermore, although the present invention is advantageously applied to the suspension link rod described above, it is also applicable to any rod in which a ball joint mechanism is incorporated in at least one end thereof, such as a stabilizer link rod for an automobile suspension. Is possible.

Although not listed here, various other modifications may be made without departing from the spirit of the present invention.

It goes without saying that the present invention can be implemented with modifications, improvements, etc.

[Brief explanation of drawings]

FIG. 1 is a front sectional view showing essential parts of an embodiment of the present invention, and FIG. 2 is a plan sectional view thereof. Figures 3, 4, 5 and 6 are respectively
FIGS. 3 and 4 are explanatory diagrams for explaining the molding operation of the embodiment shown in the figure, and FIGS. 3 and 4 are respectively similar to FIGS. This is a diagram corresponding to Figure 2, and Figures 5 and 6 are
FIG. 4 is a diagram corresponding to FIG. 3 and FIG. 4, respectively showing the flow state of the synthetic resin material during the molding operation. 10: Rod portion 14: Inner cylindrical fitting 16: Race fitting 18: Sliding resin 22: Link portion 23: Ball joint portion 26: Spherical convex surface 28: Spherical concave surface 30: Through hole 32, 34, 36: Molding mold 38 Two synthetic resin materials

Claims (1)

[Scope of Claims] A rod with a ball joint that has a ball joint at at least one end of a rod made of a synthetic resin material, wherein the ball joint has a spherical convex surface on an outer peripheral surface of an axially intermediate portion. Further, an inner cylindrical metal fitting into which a predetermined pivot shaft is inserted, a spherical concave surface corresponding to the spherical convex surface of the inner cylindrical metal fitting on the inner circumferential surface of an intermediate portion in the axial direction, and located on the outside of the inner cylindrical metal fitting, A through hole opening in the spherical concave surface is formed between the inner cylindrical metal fitting and the spherical convex surface to form a uniform gap along the spherical convex surface, and is embedded and held in the end of the rod part on the outer peripheral surface. a cylindrical race member provided therein, and a synthetic resin material constituting the rod portion flowing into the gap between the spherical concave surface of the race member and the spherical convex surface of the inner cylinder fitting through the through hole of the race member. A rod with a ball joint, comprising: a sliding resin integrally formed with the rod portion and slidably holding a spherical convex surface of the inner cylindrical fitting on an inner circumferential surface thereof.