DE7148954U - Multiple plain radial bearings - Google Patents

Description

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PATENT LAWYERS HELMUT SCHROETER KLAUS LEHMANN DIPL.-PHYS. DIPU-INC.

§ β MÖNCHEN 26 · LIPOW8KY8TR. IO

gle-9 22.1 ^ .1971 sliding bearing society cabH. 'S / BI.

Multiple sliding surface radial bearings

The invention relates to a multiple sliding surface radial bearing (preamble of claim 1).

Such multi-surface radial bearings are known from DT-OS 1 813 781. When the shaft rotates, part of the Lubricant is fed into the lubricating wedge gaps, whereby a radial pressure is built up on each of the sliding surfaces becomes »which keeps the shaft at a distance from the sliding surfaces. So-called hydrodynamic lubrication is created in which the shaft is carried by the lubricant. At rest, however, the shaft rests on each of the lowest bearing blocks Bearing on, so directly touches their sliding surfaces. In the case of multi-sliding surface bearings that are exposed to a surface pressure of more than 2o kp / cm when stationary, the result is an undesirably high friction when the shaft begins to rotate, so that an undesirably high torque for driving the shaft is required.

It is also known, in the case of cylindrical plain bearings without hydrodynamic lubrication, when the shaft is approached from below supplying lubricant under high pressure, i.e. lifting the shaft hydrostatically.

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This measure has so far not been used in multi-slide bearings for various reasons. To transfer a There must be sufficient upward force from the lubricant supplied under pressure, namely, lubricant pockets of considerable diameter are provided, through which the sliding surfaces are interrupted. This is with cylindrical Plain bearings are harmless, but have a considerable disruptive effect if sliding surfaces are used for hydrodynamic lubrication suitable multi-slide bearing would be interrupted. The remaining sliding surface can then become too small. Then the flow of lubricant in the lubricating wedge gaps is disturbed in such a way that the hydrodynamic load-bearing capacity is greatly reduced and there is a risk that the rotating shaft will come to rest on the lower sliding surfaces.

The aim of the present invention, while avoiding these disadvantages, is to achieve a hydrostatic lift-off even in the case of multiple sliding surface bearings of the type mentioned above can be made applicable with hydrodynamic lubrication. This is done according to the invention characterized in that (characteristic of claim 1).

When the shaft starts up, lubricant is introduced into the high pressure pockets under high pressure (e.g. loo atü), which causes the Shaft lifted slightly, thereby eliminating the friction of the shaft on the sliding surfaces of the adjacent bearing blocks will. At lower speeds, the rotating shaft is driven by the lubricant in the lubricating wedge gaps as well as also kept at a distance from the sliding surfaces by the lubricant from the high-pressure tips.

The sliding surfaces are not interrupted by the high pressure pockets and retain their full load-bearing capacity. In the range of sufficiently high speeds, the high-pressure pockets are no longer supplied with lubricant. In addition, the high pressure collapses immediately when the shaft is lifted after starting. The flow conditions on the sliding surfaces

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are not affected by this.

An embodiment of the invention is described below with reference to the drawings.

Fig. 1 shows a four-sliding surface radial bearing in view, with breakouts with perpendicular cuts across the shaft.

Pig. 2 shows the lower half of this bearing in plan view from plane A-A in FIG. 1.

The bearing has a support ring 2, which consists of a lower and an upper half, which lie against one another in the plane A-A. Both halves are screwed together with screws 4. In the support ring sit four bearing blocks 6, whose Sliding surfaces 8 have the radius R, while the shaft Io to be supported has the slightly smaller radius r. The support ring 2 is pierced by holes 12 for the supply and discharge of lubricant during normal operation.

Viewed from the bearing axis 11, the sliding surfaces are circular. The bearing blocks 6 are arranged symmetrically to the center plane 9. In the free spaces between the two lowest Bearing blocks and the outer edges 13 of the support ring are for hydrostatic lifting of the shaft two high-pressure tanks 14 are provided. The pockets, with a round cross-section, are made in Bores 15 provided in the support ring 2 are used, which have a counterbore 16. Inside the flat countersink is a Introduced pin 17, which engages in a recess on the high pressure pocket and secures the pocket against rotation.

The high-pressure pocket provided with a shoulder 18 has a bore 2o with a thread cut at the lower end 22 for connection to a high pressure line for the lubricant, especially OeI. The bag has one at the top

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Flat countersink 24, through which a circular ring-shaped edge surface 26 results. This edge surface is processed after the insertion of the pocket in the support ring so that the. wave lies tightly on the edge surface. At rest, the shaft also rests on the sliding surfaces 8 of the two adjacent ones Bearing blocks in a line.

The high pressure line is between a pump and the high pressure pockets a controllable valve installed, which is controlled depending on the speed. When approaching the shaft the valve is opened and it closes by itself, if in the range of higher speeds of the through the lubricating wedge gaps The built-up radial pressure is sufficient for hydrodynamic lubrication. As a result, the hydrodynamic lubrication process at nor Once the shaft is running, it is no longer disturbed by the permeating agent flowing in from the pockets under high pressure.

The hydrostatic pressure of the lubricant is about that Four times the specific surface pressure of the stationary shaft on the sliding surfaces 8.

Claims (2)

-5- gle-9 PROTECTION ON P RULES 1. Multi-sliding surface radial bearing with more than two bearing blocks, which are held in a non-rotatable manner in a support ring are that their sliding surfaces protrude slightly over the inner surface of the support ring and the sliding surfaces for Formation of lubricating wedge gaps have a larger radius of curvature than a shaft to be stored in it, as well as with a lubricant circuit, characterized in that in the position of use of the bearing two lowest bearing blocks (6) symmetrically on both sides of an imaginary, vertical center plane (9) through the Bearings are arranged and have such a, in particular round, cross-sectional shape that between them and the Edges (13) of the support ring (2) result in free spaces in each of which a high-pressure lubricant pocket (14) is arranged is, the axis of which lies at least almost in the aforementioned central plane. 2. Mehrgleitflächen-radial bearing according to claim 1, characterized in that the shaft (lo) facing Edge surface (26) of the lubricant high-pressure pocket (14) is concave and cylindrical transversely to the axis of the high-pressure pocket is that its radius of curvature corresponds to the radius (r) of the shaft, and that at rest the axis of the edge surface with which the wave coincides.