JPH0330004B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention comprises a ball head having a shaft portion on which tensile force and compressive force act approximately on its axis, and two bearings rotatably supporting this ball head. One of the bearing metals has an opening with respect to the shaft portion, the dividing plane between both bearing metals is located approximately perpendicular to the shaft portion or the load direction, and there is a gap or a gap between the two bearing metals. This invention relates to universal ball joints, especially for test equipment such as:

The well-known universal ball joint (West German patent application publication no.
1916579), the bearing or the bearing ring is formed to be elastic. Such joints are not applicable to large forces and have no compliance. For example, in the case of ball joints used in test equipment, there must be no play when the direction of the force changes (tension-compression). Nevertheless, the joints must be easily movable and must transmit large test forces.

The object of the present invention is to provide a universal ball joint, especially for use in test equipment, which is capable of transmitting large dynamic forces, is easy to follow and has low friction in the joint, i.e. can be moved easily. It's about getting. This purpose is the first claim.
This can be achieved by the means described in the characteristics section of the section.

By using tightening and loosening elements for tightening the two bushings against each other and against the ball head, the play of the joint can be easily adjusted and, if necessary, can be made to follow. Moreover, in particular by pretightening the clamping element, the dynamic loads on this clamping element can be kept very low. If there is no load-relieving or loosening element, the tightening element must be designed several times larger to transmit the same force. Furthermore, an auxiliary locking device for the tightening element is required to prevent this element from loosening.

It is advantageous for the tightening and loosening elements to be designed as bolts, which facilitates adjustment and follow-up adjustment of the bearing. Instead of the loosening bolt, it is also possible to use suitably designed spring elements or intermediate elements whose spring constant is greater than the spring constant of the tightening bolt. In order to improve the wear and/or friction properties, the ball head and/or bearing ring can be provided with a coating layer having an advantageous coefficient of friction and wear. Advantageous embodiments of the invention are described in the subclaims.

The present invention will be described in detail below based on embodiments shown in the drawings.

The ball joint according to FIG. 1 has a ball head 1 with a shaft 2 to which force-transmitting elements (not shown) can be connected for introducing tensile and compressive forces (±F). This ball head 1 has a shaft portion 2
It is housed between an upper bearing metal 3 which receives a tensile force and a lower bearing metal 4 which receives a compressive force. One upper bearing metal 3 has an opening through which the shaft portion 2 passes. The other lower bearing metal 4 is connected to, for example, a structural component to be tested. The dividing plane between the two bearings 3 and 4 is located approximately perpendicular to the load direction (force ±F) or the axis of the shaft portion 2.

The two bearings 3, 4 are fastened to each other and to the ball head 1 by means of a tightening bolt 5 which is arranged on the upper bearing 3. The size and number of the tightening bolts 5 and the tightening force of the tightening bolts 5 are determined in such a way that the static and dynamic loads occurring in the ball joint can be transmitted satisfactorily.

The tightening force of the tightening bolt 5 on the ball head 1 is partially loosened by a loosening bolt 6 provided on the lower bearing 4 and pressed against the upper bearing 3. 4 until a desired gap or desired slack is formed. In this case, the clamping bolt 5 is pulled more tightly. This large tensile force ensures that the dynamic operating loads on the tightening bolt 5 remain small under all dynamic loads, such as repeated or alternating loads.
The clamping bolt 5 is only exposed to a small additional load. In this case, the dynamic load is absorbed by the tightening bolt 5 and the loosening bolt 6, and the universal ball joint follows the dynamic load without play. This also applies if the clamping bolt 5 is tensioned by a vertical spring element, by an intermediate element or by another suitable method.

When wear occurs, the ball head 1 and bearing metal 3,
4 can also be adjusted by following the loosening bolt 6. For this purpose, the loosening bolt 6 is loosened until the desired gap in the ball joint is again formed.

In order to keep the bearing friction as low as possible, the ball head and/or bearing rings 3, 4 are designed, for example
A sliding layer 7 made of a suitable material such as PTFE (polytetrafluoroethylene), polyimide, bearing bronze, etc.
is covered.

The size and number of the loosening bolts 6 and the supporting length of the loosening bolts 6 are determined so that the loosening bolts 6 form a vertical spring as much as possible. In this case, the supporting length of the loosening bolt 6 means the free length of the bolt between the two bearings 3 and 4.

In contrast to the drawing in FIG. 1, the tightening bolt 5 and the loosening bolt 6 can also be arranged in one of the bearing brackets, that is, either the upper bearing bracket 3 or the lower bearing bracket 4.

FIG. 2 shows an arrangement in which the tightening or loosening bolt is replaced by a screw in one of the bearings and a suitable counter-screw arrangement.

In FIG. 2, the upper bearing 3 has a screw 8 on its outer periphery, and the upper bearing 3 is inserted into the threaded ring 9 by this screw 8. The upper bearing 3 is fastened to the ball head 1 or the lower bearing 4 by a tightening bolt 5. Upper bearing metal 3
is adjusted in the same way as the loosening bolt 6 by means of a threaded ring 9, or the tightening force of the tightening bolt 5 is applied. The upper bearing 3 is inserted into the lower bearing 4 by a screw 8 and is tightened to the ball head 1 or the lower bearing 4. By means of the loosening bolt 6 the ball joint is adjusted in the same manner as described in FIG.

As described above, the present invention uses a combination of play adjustment tightening bolts and loosening bolts on the bearing metal of a universal joint to easily follow the dynamic load applied to the universal joint, and furthermore, the load transmitted to the tightening bolt is small. Therefore, the bearing part can be made smaller by reducing the number of tightening bolts, and the play adjustment can be made easier.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a ball and socket joint according to the invention, and FIG. 2 is a sectional view of different embodiments of the ball and socket joint according to the invention. DESCRIPTION OF SYMBOLS 1... Ball head, 2... Shaft part, 3, 4... Bearing metal, 6... Loosen bolt, 7... Sliding layer, 8... Screw,
9...Screw ring.

Claims (1)

[Scope of Claims] 1. A member having a ball head 1 and a rod-shaped shaft portion 2; a lower bearing metal member 4 having an inner spherical recess that makes spherical contact with the ball head 1 and receiving compressive force acting on the shaft portion 2; , has an inner spherical recess, and has an opening at the bottom of the recess through which the shaft portion 2 passes;
An upper bearing metal 3 receives a tensile force acting on the shaft part 2. While the shaft part 2 is inserted into the opening of the upper bearing metal 3, the ball head 1 connects the upper bearing metal and the lower bearing metal 3, 4. A universal ball joint rotatably held between the upper bearing metal 3 and the upper bearing metal 3.
A tightening element 5 for forcibly narrowing the gap between the upper bearing 3 and the lower bearing 4 and a loosening element 6 for forcibly widening the gap between the bearings are provided on at least one of the lower bearing 4 and the upper bearing 3 and the lower bearing 4. While the tightening element 5 and the loosening element 6 apply forces in opposite directions to each other, the upper bearing bracket 3 and the lower bearing bracket 4 are
A universal ball joint characterized in that the distance between 〓 and 〓 is maintained at a predetermined value. 2. Universal ball joint according to claim 1, characterized in that the clamping element is designed as a clamping bolt 5. 3. The load relief and/or loosening element is formed as a loosening bolt 6, which is arranged on one bearing 3, 4 and on the other bearing 4,
3. The universal ball joint according to claim 1 or 2, wherein the universal ball joint is abutted and supported by the joint member 3. 4. The universal ball joint according to claim 2 or 3, characterized in that the tightening and loosening bolts 5, 6 are arranged on the same bearing metal. 5. The universal ball joint according to any one of claims 2 to 4, wherein the length of the tightening bolt 5 is longer than the supporting length of the loosening bolt 6. 6. The universal ball joint according to claim 1, wherein the loosening element is formed as a spring with a spring constant larger than that of the tightening bolt 5 or as an intermediate element. 7. Any one of claims 1 to 6, characterized in that a coating layer 7 having frictional and wear characteristics is provided on the bearing surface of the ball head 1 and/or the bearing metals 3 and 4. The universal ball joint described in item 3.