DE2742536A1 - SLIDING BEARING ELEMENT FOR HIGHLY LOADED BEARING POINTS - Google Patents

Description

27A2536

Miba Gleitlager Aktiengesellschaft, Laakirchen (Austria)

Plain bearing element for heavily loaded bearing points

The invention relates to a plain bearing element for heavily loaded bearing points with a layer of bearing metal based on aluminum or copper and white metal embedded in superficial depressions in this layer.

It is well known that the sliding properties of white metal are much more favorable than those of a bearing metal based on aluminum or copper. However, white metal has a comparatively low strength, which is why it is used if white metal is used as a running layer alone, there is a risk that fatigue fractures will occur under high bearing loads. If, on the other hand, the white metal is in superficial depressions of the much stronger layer of bearing metal embedded on an aluminum or copper basis, the latter has a supporting effect that increases the load-bearing capacity, In addition, the webs remaining between the depressions cause a crushing deformation of the white metal inclusions prevent under the load.

It has now been shown that, for example, with crosshead bearings of large engines, especially two-stroke engines, Difficulties arise despite the use of such slide bearing elements. In two-stroke engines are namely before Above all, the crosshead bearings exposed to unfavorable operating conditions, because on the one hand due to the two-stroke process no investment change takes place and on the other hand because of

809813/0881

The low sliding speed resulting from the small angular movement does not have a stable lubricating film arises. The lack of a stable lubricating film has an increased proportion of mixed friction and accordingly result in high heat generation, even if part of the running surface is made of white metal, since the webs are made of the bearing metal with the less favorable sliding properties participate in the friction process. The danger of rubbing is especially given when a new machine is running in because the bearing component of the bearing element is still is low and therefore high local pressure peaks occur.

Thus, the invention is based on the object of eliminating these deficiencies and that described above To improve sliding bearing element so that it has favorable sliding properties, especially when retracting.

The invention solves the problem in that the webs between the white metal inclusions opposite whose surface forming the tread is recessed.

Since the web surface is not up to the non-ferrous metal surface is enough, at least during the retraction, only that comes with regard to its sliding properties much cheaper white metal to the effect. In addition, however, result from the recessed webs between the white metal inclusions are grooves in which the lubricant even with metallic contact between pins and white metal can remain stored.

In order for these grooves to serve as a lubricant reservoir, however, there must be sufficient liquid from the outset Lubricant must be available. In order to avoid bearing damage even in extreme cases in which there is a lack of lubricant To be able to avoid inadequate lubrication with certainty, in a further embodiment of the invention, the Grooves over the webs with an optionally synthetic resin-bonded one Dry lubricant must be filled out. The dry lubricant present in the grooves, the

809813/0881

for example from polytetrafluoroethylene, molybdenum disulfide, graphite or the like. can exist, prevents Failure or interruption of the liquid lubrication. A rubbing of the bearing, so that the desired Fault bridging results.

Plain bearing elements of the type according to the invention are usually manufactured in such a way that in the bearing metal on aluminum or copper base the indentations are embossed and then the entire bearing metal layer Doused with the white metal or galvanically coated is, after which the white metal is mechanically removed until the webs come to light. Be according to the invention now the webs between the white metal deposits deepened by etching, so that a relatively simple and cheap manufacturing possibility results.

In the drawing, the subject matter of the invention is shown, for example, purely schematically, namely show Fig. 1 shows a sliding bearing element according to the invention in section without groove filling and

FIG. 2 shows an illustration, corresponding to FIG. 1, of a slide bearing element with a groove filling. The slide bearing elements shown consist of a support body 1 made of steel on which a layer 2 made of bearing metal is applied on an aluminum or copper basis. In superficial depressions 3 of this layer 2 is White metal A stored. The webs 5 between the white metal inclusions are opposite to the running surface forming surface of the inclusions 4 deepened, so that according to FIG. 1 at least when entering the camp only the white metal surface comes into effect and 5 grooves for lubricant storage are formed over the webs.

According to FIG. 2, the grooves above the webs 5 are filled with a dry lubricant 6, which ensures the bearing lubrication even if there is a lack of liquid lubricant or if the liquid lubricant film is interrupted.

809813/0881

e e r e i t e

Claims (3)

Patent attorney Dipl-Ing. H. Lamprecht 6 Munich 5 Patent claims: Plain bearing element for heavily loaded bearing points with a layer of bearing metal on aluminum or copper base and white metal embedded in superficial depressions in this layer, characterized in that the webs (5) between the white metal deposits (4) opposite the The surface forming the tread is recessed. 2. plain bearing element according to claim 1, characterized characterized in that the grooves over the webs (5) with an optionally synthetic resin-bonded dry lubricant (6) are filled out. 3. A method for producing a plain bearing element according to claim 1, characterized in that that the webs (5) between the white metal deposits (4) are deepened by etching. 80931 3/088 1 ORIGINAL INSPECTED