DE1021211B - Universal joint bearing - Google Patents

Description

Universal joint mounting Universal joints, which consist of the cross member, the Needle bearing bushes and forks exist, have a relative mass as a circumferential mass great weight that brings with it many known difficulties. The size of one The universal joint is determined by the forces to be transmitted.

Needle sleeves, which are used to transmit the oscillating movements form the bearing point., are mainly machined, hardened and Ground on the outside and inside diameter as well as on the floor, so that the required Accuracy for the seat in the fork, for the enveloping circle diameter of the needles and the ground clearance is reached. The manufacturing process required for this requires a large wall thickness, either a smaller pin diameter or a a smaller wall thickness for the fork eyes or, on the other hand, a larger total weight of the joint cross results.

The thick-walled sleeves are particularly rigid and lead to the relatively elastic construction. of the universal joint forks to very high edge pressures in the camps. When pressing such thick-walled sleeves into the fork must be very Great care should be taken to avoid larger oversizes, as larger Pressing an unfavorable preload of the fork material rushes. In to loose fit of such sleeves is the risk of displacement of these sleeves in the Fork is present despite being axially secured. The demand for the lowest possible Pressing, but on the other hand after a tight fit as possible, forces to strong Narrowing of the tolerances and thus making the bushings and forks more expensive.

In order to increase the breaking strength of such needle barrels, is predominantly Insert material selected, which is inserted about 0.8 to 1.0 mm deep and then hardened will. Because of delay and subsequent grinding, a great depth of use must be aimed for which, however, increases the risk of breakage, especially in the ground, of which Strength and weight especially enter into the effective mass forces and therefore should be kept as weak as possible.

Often, grooves and shoulders must be in such bushings after insertion be stabbed to reduce the risk of carburization and overcarburization Avoid cross-sections.

Joint crosses including needle bushings need to be flawless Function a close tolerance of the measure for the ground clearance of two opposite ones Bushes, which is made up of the length of the joint cross and the thickness of the base of the bushing composed. In the known universal joint sleeves are therefore difficult, in particular costly grinding operations required to make the floor dimension the necessary Achieve tolerance.

Another difficulty with such machined needle bushings for joint crosses is the attachment of the necessary seals. Because the tolerances are very large due to the turning process and the subsequent heat treatment, are additional holding means, such as sheet metal caps; for attaching the seals required or must the. Seals mounted separately as independent elements will.

Due to the inaccuracy of the position of the seals, it is necessary to Provide thrust washers for the needles on the open side of the sleeve. they form additional components and extend the assembly time.

The radial needle roller bearing is supplied with grease from a bore in the center of the pin, which is provided with cross-shaped grooves on its end face is. These grease grooves are created by milling and result when sliding on the The bottom of the needle barrel has a very disadvantageous scraping effect with dangerous abrasion, which can also be avoided entirely by very careful deburring.

In the more recent development of needle roller bearings, needle sleeves have become known, which are manufactured without cutting. These sleeves are used for shaft ends. on those at the same time a seal is to be achieved, executed with a closed bottom. The wreath in these rifles is partly with, partly without Cage used.

The invention now provides a solution which overcomes the deficiencies mentioned and results in significant technical and economic advantages.

According to the invention, a universal joint bearing is proposed in which the liners made of elastic acting. in per se known VVeis, e drawn and hardened ground boxes with needles are made and in the open Ends of the liner seals are used, which at the same time as a run-up serve for the end faces of the needles.

The invention makes it extremely convenient and easy to manufacture simple universal joint mounting created.

It is known that the liners for needle roller bearings with liners to manufacture as drawn and hardened bottom sleeves and the free ends of the liners flanging so that they also act as a run-up for the end faces of the needles to serve. The use of such liners for a universal joint bearing would but a special seal against the open ends of the liners make the pin necessary, what in the formation of the open ends of the known Ground boxes would cause particular difficulties. For creating one It is important that in the open, it is not appropriate that the crucifixion is appropriate flanged ends of the liners are used directly seals that at the same time as a run-up for the end faces of the needles. to serve. With the drawn ones Bushings can be used in one end operation at the same time because of the predominantly chipless nature reshaped seat for the seal necessary for a favorable seal Create the conditions. While the thick-walled, machined ones Büchsen large inaccuracies with regard to the absolute dimension and the concentric The run of the seal seat to the needle raceway is unavoidable from a manufacturing point of view, When the bushes are drawn, the raceway and the seat for the seal are in one Operation when pulling over the mandrel in the inevitable concentricity and high accuracy achieved. The distortion from the heat treatment is also reduced by the Pressing into the fork eye in the same way for the raceway and for the seat surface the needles lifted. The thin-walled sleeve allows, especially in the not full cured state of their open side in a simple manner a slight flanging perform and thus to secure the sealing ring axially.

It is particularly useful if the bottom of the liner has a smaller one Hardness and higher elasticity than the needle raceway. This lets through partial hardening or partial tempering in a technically easier and cheaper way Way to achieve.

Finally, it is proposed that indentations be made in the bottom of the liners to be arranged running in a predominantly radial direction, which reinforces the Cause soil and at the same time can serve the lubricant passage.

Further details of the invention are illustrated in the drawings examples shown. 1 shows a longitudinal section through a universal joint bearing with thin-walled needle sleeve and inserted seal, FIG. 2 is a longitudinal section by means of a universal joint bearing with needle bushing with corrugations in the bottom according to line II-II 3, 3, a view of the bottom of the needle barrel according to FIG. 2, FIG. 4 shows a longitudinal section through a universal joint bearing with a thin-walled bottom socket and inserted axial disk needle bearing, Fig. 5 shows the special design of a cage for an axial disk needle bearing, FIG. 6 shows the cage according to FIG. 5 on an enlarged scale in section along line VI-VI of FIG. 5.

In Fig. 1, 1 is the joint cross with its designed as a needle raceway 2 Pin 3. The outer raceway for the needles 4 forms a thin-walled sleeve 5, whose needle track 6 has the hardness and load-bearing capacity necessary for the load.

The bottom of the needle barrel 5 is provided with an outer recess 7. The inner surface of this bottom part results in the contact surface 8 for the journal face 9. Radial grooves 10 are incorporated into the journal face, which the lubricant can pass through serve from the central bore 11 to the needle roller assembly.

A sealing ring 13 is inserted into the open sleeve side 12, which forms the run-up for the needle tips on the end face 14 and on his inner diameter 15 seals against the pin jacket. An additional seal is achieved when the end face 16 of this seal, which is thin and elastic, runs against the end face of the joint cross pin or with it a gap seal results.

In Fig. 2, the needle barrel is provided with beads 17 and the pin end face 18 designed smooth. The lubricant passage from the pin bore 11 to the needle roller and cage assembly happens through the beads in the bottom of the needle box. These beads will be shown in Fig. 3 in the view from the inside of such a bottom box. There are in this case four extending in the radial direction from the center to the needle roller assembly Beads provided. The needle sleeve according to Fig. 2 is hardened only in the field of needles 19, while the open end face 20, on which the seal 13 sits, and parts of the Bottom 21 are uncured to increase the elasticity.

The embodiment according to FIG. 4 corresponds essentially to that according to Fig. 1. To absorb the axial forces of the universal joint pin on the bottom of the Bushing is a needle disk bearing 22 used, the needles 23 in a cage 24 are performed. For this purpose, the end face 25 of the pin is without lubrication grooves formed and, like the bottom surface of the sleeve 26, serves directly as a running surface for the needles. It is also possible, as known for thrust washers, either a suitable one on the bottom side of the bushing or on the face of the pin Use a raceway disc for the needles. A washer on the bottom side of the Bushing means at the same time a stiffening of the needle bushing base.

A design of such a needle cage is shown in FIGS. 5 and 6 shown. The needles 23 are located in a disc cage 27, which is predominantly is kept as strong as the needle diameter, but at parts of its circumference in z. B. has grooves 28 extending in the radial direction of small depth, so that the Lubricant can get from the center of the joint cross pin to the needle roller and cage assembly.

Claims (5)

PATENT CLAIMS: 1. Universal joint bearing, characterized in that the liners are made of elastic acting, drawn in a known @, N'eise and hardened.eii ground boxes are made of finite needles and inserted into the open ends of the Liner seals are used, which also act as a stop for the end faces the needles serve. 2. Universal joint bearing according to _ @ irspruch 1. as indicated by, that the bottom of the liners has a lower hardness and higher elasticity than that Owns a needle track. 3. Universal joint mounting according to claim 1 and 2, characterized in that the open ends of the liners have a smaller one Have hardness and greater elasticity than the raceways. 4. Universal joint bearing after Claims 1 to 3, characterized in that recesses in the bottom of the liners run in a predominantly radial direction, which cause stiffening of the floor and at the same time can serve for the passage of lubricant. 5. Universal joint bearing according to claim 1 to 4, characterized in that the axial pressure of the pin is added against the bottom of the liner by a thrust washer needle bearing.