AT392522B - SLIDE BEARING ELEMENT WITH INHOMOGENIC ANTIFRICTION LAYER - Google Patents

Description

AT 392 522 B

The invention relates to a slide bearing element with an inhomogeneous antifriction layer, consisting of a support layer and a support layer made of bearing material applied to the support layer and having essentially axial spacing from one another, essentially parallel, at least over a part of the sliding surface, filled with a slide bearing material and filled with a groove-like recesses , wherein the bearing material of the base layer has a lower or greater hardness than the plain bearing material filling the groove-like depressions, for example radial plain bearings with axially spaced circumferential recesses in the base layer filled with plain bearing plastic

From AU-PS 143 992, in particular Fig. 5 and the associated parts of the description, a plain bearing with an inhomogeneous anti-friction layer is known, specifically with a helical groove arrangement extending in the circumferential direction of the plain bearing. These grooves are filled with a soft plain bearing plastic, which has only a low load-bearing capacity, but has good friction properties. The dimensions of the grooves should be adapted to the different operating conditions in accordance with AU-PS 143 992. However, no information is given about the actual adaptation to the operating condition oil

From AT-PS 323 476 an antifriction element, in particular a plain bearing is known, which is designed as a monolithic pressed part, in which the construction polymer of the phenolic type, filled with rigid clunches of the type such as graphite, bomitride, molybdenum sulfide, or a mixture of these substances, alternately , Polyester, polyheteroarylene, polyolefins, polyphenyls or the like. Materials consisting of self-lubricating plastic sections are arranged. AT-PS 323 476 also does not provide any information about the dimensions of the depressions in the base layer filled with solid lubricant

Furthermore, it is known from EP-PS 57 808 and US-PS 4,400,099 to embed a softer bearing material in a groove-like depression of a harder bearing material layer which extends essentially in the running direction in order to combine the advantages of a harder bearing material with the advantages of softer sliding bearing materials To connect plain bearings. Since the spacing of adjacent recesses ensures a fine distribution of the harder and softer bearing material over the tread width, the individual bearing materials come into effect not only in a local load area, but also in their combination, so that the disadvantages of the individual separate bearing materials are essentially turned off. The bearing material layer made of a harder material takes on a supporting function which relieves the softer material relatively, which results in an increase in the fatigue strength and wear resistance. With regard to their emergency running properties, plain bearings of this type therefore behave largely like bearings with a continuous running layer made of a softer bearing material, but have the advantage of a significantly lower wear compared to these latter bearings. The plain bearing known from EP-PS 57 808 and US Pat. No. 4,400,099 is said to provide favorable operating results with regard to wear and fatigue, because the groove dimensions, such as width, depth and distance, are determined in a certain dependence on the bearing diameter.

Practice has shown, however, that due to the extremely wide-spaced maximum and minimum ranges of the groove dimensions, there is no optimal distribution of the soft and hard load-bearing components, even in middle areas. Bearings of this embodiment are therefore not suitable to meet the high demands placed on and expected of them, since other important criteria have been neglected. For example, it was disregarded that bearings with a certain diameter can be subjected to completely different loads and that the bearing diameter as a reference variable alone is therefore in no way suitable for defining measures to reduce wear and fatigue in a manner that is sufficient for practical use.

FR-PS 2 157 072 addresses the load dependency of the construction, but does not teach how the load dependency should be taken into account.

The object of the invention is therefore to provide a heavy-duty slide bearing with an inhomogeneous anti-friction layer, which fully meets the requirements to be placed on a heavy-duty slide bearing and thereby creates the possibility of taking the measures to be used to reduce wear and tear due to the specific measures provided in the respective case Determine the bearing load clearly and reproducibly beforehand.

This object is achieved according to the invention by the features contained in the characterizing part of claims 1 to 3

The measures listed in the characterizing part of claim 1 are no longer related to the bearing diameter, but to the specific bearing load, which results as follows: p = specific bearing load [N / mm ^]

F P = -

D.B F = bearing force (load) in [N] D = nominal bearing diameter in [mm] (inner diameter) B = load-bearing layer width in [mm]. -2-

AT 392 522 B

With the specific bearing load p used according to the invention to determine the dimensioning of the depressions, the lubricating film pressure in the plain bearing also becomes decisive for the dimensioning of the groove-like depressions filled with other plain bearing material. It has been shown in the context of the invention that the level of the specific loads has a considerable influence on the specifications for the groove-like depressions. This applies on the one hand to the intended specific load of the slide bearing and on the other hand also with regard to the specific load capacity of the bearing material for the base layer, which is naturally selected in accordance with the intended use, and the slide bearing material, which is also selected from such points of view, for the failure of the groove-like depressions. In a particularly advantageous development of the invention, mathematical relationships for the determination of the width (b) of the groove-like depressions, the web width (s) remaining between the groove-like depressions, the ratio of the groove width (b) to the web width (s) due to the resilience of the Set up the selected bearing material for the base layer and the specific bearing load actually envisaged. Similarly, mathematical relationships can be found for the groove depth (t) of the recesses and for the ratio of the groove width (b) and the groove depth (t) of the groove-like recesses depending on the load-bearing capacity of the plain bearing material selected for filling the groove-like recesses and the specific intended actually Set up bearing load.

The invention can be used both in the case of simple groove-like, extending in the running direction of the recesses and in the formation of the recesses in a plurality of groups, for example two intersecting groups of groove-like recesses, even if the mutual spacings of the groove-like recesses in the different groups should be different from each other.

Experiments have shown that when the intended specific bearing load is taken into account when dimensioning the groove-shaped depressions according to the invention, optimum results are achieved with regard to fatigue strength, wear and emergency operation.

Exemplary embodiments of the invention are explained in more detail below with reference to the drawing, in which:

1 is a perspective view of a slide bearing according to the invention formed from two slide bearing shells;

2 shows a plain bearing according to the invention in the form of a bearing bush;

3 shows a diagram with the parameters essential for calculating the area of the bearing running surface provided with depressions;

Fig. 4, the area (5) of Figure 1, greatly enlarged.

Fig. 5 shows the area (5) of Figure 1 in a modified version, greatly enlarged.

Fig. 6 is a greatly enlarged plan view in area (5) of Fig. 1;

7 shows a plan view corresponding to FIG. 6 in a modified embodiment of the invention;

FIG. 8 shows a plan view corresponding to FIG. 6 in a further modification of the invention;

9 shows a one-piece flange bearing shell designed according to the invention; and

10 is a perspective view of a bearing shell and two semi-annular thrust washers for a bearing arrangement according to the invention;

In the example in FIGS. 1 to 8 there is a slide bearing (20), for example in the form of two bearing shells (21) and (22) or in the form of a slide bearing bush (23), which is seamless or also curved and is formed with an axial slot (24) can, on the bearing running surface (25) with groove-like depressions (26) in the support layer (27).

In the example in FIG. 1, the slide bearing (20) is formed from two slide bearing shells (21) and (22) which have groove-like depressions (26) in their base layer (27). Various embodiments are possible for the groove-like depressions (26), for example grooves running in a circular manner, as shown in a top view in FIG. 6. The groove-like depressions (26) could also be helical with a small pitch angle of up to 15 °. Between the groove-like depressions (26) and the webs (29) which have remained between them, the following parameters are essential, as can be seen particularly from FIG. 3: (a): the distance from the web center to the web center; (b): the recess width in the area of the sliding surface; (s): the remaining web width in the area of the sliding surface; (t): the recess depth.

Of the ratios derived from these parameters, the relation of the recess width (b) to the remaining web width (s) is particularly important. For the calculation of these parameters and the relation of recess width (b) to the remaining web width, minimum values, maximum values and mean values based on the specific bearing load (p) have to be determined, where _ Λ p [N / mnr6] is to be calculated from F = bearing force ( Load) in [N], D = bearing diameter in [mm] (inside diameter) B = load bearing width in [mm] according to the formula: -3-

AT 392 522 B

F P = -

D.B

The following are to be calculated on this grand location: a) width (b) in fyun] of the groove-like depressions or recesses (26); for heavy-duty base courses, d. H. Base layers with a load capacity above about 50 N / mm2 based on p + 20 the projected storage area, equal or smaller, preferably equal to bmaT = 200-P +12.5 for lightly resilient base layers, i.e. H. Base layers with a load capacity below about 35 N / mm2, based on p + 20 on the projected storage area, the same or greetings, »preferably equal to bmin = 56.25- p +12.5 for medium-duty base layers, i.e. H. Base layers with resilience between about 30 and about p + 20 Λ 55 N / mm, based on the projected storage area, small or larger, preferably equal to bmit = 75- p + 12.5 b) the remaining web width (s) in [pm ]: for lightly bearing base layers, d. H. Base layers with a load capacity below about 35 N / mm2, based on the projected storage area, equal or smaller, preferably equal to 2050 (p + 20) smax = “118.06 + 9.652. p + 6.528.10 * 2. p2 + 3,889.10,3. p3 for heavy-duty base layers, i.e. Base layers with a load capacity above about 50 N / mm2, based on the projected storage area, equal or greater, preferably equal to 525 (p + 20) smin = 118.06 + 9.652. p + 6.528.10'2. p2 + 3,889 .10,3. p3 for medium load bearing layers, d. H. Base layers with a load capacity between about 30 and about 55 N / mm, based on the projected storage area, smaller or larger, preferably equal to 750 (p + 20) smit ~ “118.06 + 9.652. p + 6.528. IO'2. p2 + 3,889.10'2. p3 c) The recess depth (t) in [pm]: for heavy-duty fillers, d. H. Plain bearing materials with a load capacity above about 40 N / mm2, 1350 in relation to the projected bearing surface, equal or smaller, preferably equal to tj ^ - p + 12.5 for low-load fillers, d. H. Plain bearing materials with a load capacity below about 20 N / mm2, 900 in relation to the projected bearing surface, equal or greater, preferably equal to t ^ = - p + 12.5 for medium-duty fillers, d. H. Plain bearing materials with a load capacity between approximately 20 and approximately -4-1125

AT 392 522 B 45 N / mm2, based on the projected storage area, small or larger, preferably equal to ^ = - p + 12.5 d) the relation of recess width (b) to remaining web width (s): for heavy-duty base layers, d. H. Base layers with a load capacity above about 50 N / mm2, based on the projected storage area, (b / s) max = (1.95 to 2.0). (1,757 + 3,1.10 * 3. P + 7,233. IO * 4. P2) for lightly bearing base layers, i.e. H. Base layers with a load capacity below approx. 35 N / mm2, based on the projected storage area, (b / s) min = (0.5 to 0.55). (0.5100 + 0.9.10'3. P + 2.1. IO " 4. P2) for medium-duty base layers, i.e. H. Base layers with a load capacity of between about 30 and about 55 N / mm2, based on the projected storage area, (b / s) with = 0.9444 + 1.6667.10'3. p + 3.8889.10 * 4. p2 and the dependence of the selected recess width (b) in relation to the recess depth (t) for heavy-duty fillers, d. H. Plain bearing materials with a load capacity above about 40 N / mm2, based on the projected bearing surface, (b / t) min - 4'167 · 10'2 · P + 0.8333 for low-stress fillers, i.e. H. Plain bearing materials with a load capacity below about 20 N / mm2, based on the projected bearing area, (b / Omax = (1> 95 to 2.0) · (10.834. IO-2. P + 2.1666) for medium-duty fillers, ie plain bearing materials with Resilience between about 20 and about 45 N / mm2, based on the projected storage area, (b / Omit = 6,667.10 * 2. P + 1333

Here it is taken into account that, in principle, not only the bearing diameter, but above all the lubricating film pressure is decisive for the dimensioning of the groove-shaped depressions of such a plain bearing. Simplified, the specific bearing load can be used instead of the lubricating film pressure. It has been shown that at high specific loads other determinations of the relevant sizes for the groove-shaped recesses (width, depth, distance) are more advantageous than at low specific loads. In particular, it has a surprising effect in connection with the selection of the bearing material for the carrier layer and the filler in the groove-like depressions on the structural design of the depressions in width and depth. In this way, the fatigue strength and wear resistance of the plain bearing can be optimally influenced. The use of different materials for the carrier layer and different fillers accordingly requires different dimensions of the depressions. The explanations above contain information on how these material properties are to be taken into account.

Tests have shown that, taking into account the dimensioning of the groove-like depressions explained above, optimum results are achieved with regard to fatigue strength, wear and emergency running.

The groove-like depressions can form closed annular grooves, but it is preferred to provide annular depressions in a helical arrangement.

As can be seen from the region (5) of FIG. 1, shown greatly enlarged in FIG. 5, the slide bearing material filling the groove-like depressions (26) can be formed beyond the remaining ribs or field (29) into a closed layer (30) . Depending on the plain bearing materials used, the -5-

AT 392 522 B

Base layer (27) and the material filling the groove-like recesses (26) and possibly forming the sliding layer (30) can be a material between the base layer (27) and the material filling the groove-like recesses (26) and possibly forming the sliding layer (30) Diffusion barrier layer or a binding layer (31) can be provided, which can have a thickness between about 0.5 and 2 μm. In contrast to this, the enlarged 5 area of FIG. 4 alternatively shows a flush termination of the ribs (29) with the sliding layer (30) or the filling of the groove-like depressions (26).

As FIGS. 4 and S also show, the supporting layer (27) is attached to a suitable substrate (32), for example a steel shell or bush.

The shape of the groove-like depressions can be different, for example the groove-like depressions (26) can be designed in the manner of a cross thread, so that between the groove-like depressions (26) there are diamond-shaped or otherwise square fields (29), as is the case here Figure 7 shows. In addition to a cross thread, the groove-like depressions (26) can also have transversely extending grooves (26a), so that triangular, remaining fields (29) result, as shown in FIG. The mutual distances between the intersecting groove-like depressions (26) are shown in Figures 7 and 8 15 as the same size. However, it is also possible to provide a different groove spacing in one group of depressions (26) than in the group of depressions (26) crossing them.

FIG. 9 shows a flange bearing shell (22a), which in its radial bearing part contains a bearing sliding surface (25) with groove-like depressions (26) in the base layer (27). One collar (35) is formed on its base layer (27) with groove-like depressions (26) which, in this example, are spiral-shaped, ie. H. are designed to widen in the circumferential direction 20. In this example, the groove-like depressions (26) could also be formed concentrically to the center axis of the bearing. As with the radial bearing part, the groove-like depressions (26) in the collar (35) are also filled with sliding bearing material, this bearing material also being able to cover the ribs or fields arranged between the groove-like depressions. The second collar (36) of the collar bearing shell (22) according to FIG. 9 can be designed like the first collar or in a conventional manner with a smooth surface of its base layer 25. To form a complete plain bearing, a flange bearing shell according to FIG. 9 is put together with a second flange bearing shell, which can be designed in the same way as that according to FIG. 9 or in a conventional manner.

The same or similar design as in a one-piece flange bearing (22a) can also be provided in such plain bearings in which the collars are designed as separate thrust washers (38) and (39) and 30 are attached directly to the radial bearing part by means of connecting straps.

The example in FIG. 10 is a bearing arrangement in which the radial bearing part is formed by two slide bearing shells (21) and (22) (FIG. 1). The slide bearing shell (22) has a bearing sliding surface (25) in which the base layer is provided with groove-like depressions (26). Axial bearing parts are used without contact with this radial bearing part, namely thrust washers (38) and (39), which are inserted into the bearing receptacle at a lateral distance from the side edges of the radial bearing part. One thrust washer (38) or both thrust washers (38) and (39) have groove-like depressions in their base layer, which run concentrically to the center axis of the bearing. Instead, spiral-shaped groove-like depressions could also be provided.

A wide variety of combinations of 40 plain bearing materials are possible in all of the exemplary embodiments described above, for example the base layer (27) can be made of lead bronze. The slide bearing material filling the groove-like depressions (26) can be white metal bearing alloy, preferably a tin-antimony alloy of the SnSb7 type can be used for this. Instead of the sliding layer (30) shown in FIG. 5, the remaining ribs or fields (29) can also be covered with a layer of lead-tin alloy or tin-antimony alloy with a thickness of 0.5 to 2 μm . 45 Another advantageous material pairing in a slide bearing shell (22) or a slide bearing bush (23) can consist, for example, in that the base layer (27) consists of an aluminum alloy, preferably AlZn4.5SiCuPbMg, and the groove-like depressions are filled with a white metal slide bearing alloy are, preferably based on PbSnCu. In such a case, a layer (31) made of nickel or CuSn will have to be provided. 50

LIST OF REFERENCE SIGNS (20) plain bearing 55 (21) plain bearing shell (22) plain bearing shell (22a) flange bearing shell (23) plain bearing bush (24) axial »slot 60 (25) bearing race (26) groove-like recesses (26a) qu» extending grooves -6-

Claims (4)

AT 392 522 B (27) Base layer (28) Bearing center axis (29) Ribs (30) Sliding layer (31) Diffusion barrier layer or bonding layer (32) Substrate / support material (35) Bind (36) Bind (38) Thrust washer (39 ) Thrust washer (a) Center-to-center distance (b) Cutout width (s) Bridge side (t) Cutout depth PATENT CLAIMS 1. Slide bearing element with an inhomogeneous antifriction layer, consisting of a support layer and a support layer made of bearing material on the support layer, which is essentially at an axial distance from one another Arranged in parallel, at least over a part of the sliding surface, has groove-like depressions filled with a sliding bearing material, the bearing material of the base layer having a lower or greater hardness than the sliding bearing material filling the depressions, for example radial sliding bearings with an axial spacing from one another in the circumferential direction Plain bearing material Filled-in depressions in the base layer, characterized in that the groove width (b) of the depressions, the web width (s) remaining between the depressions and the ratio of groove width (b) to web width (s) for heavy-duty base layers, d. H. Base layers with a load capacity of above about 50 N / mm1, based on the projected bearing area, are coordinated as follows: a) Groove width (b) [pm] equal or smaller, preferably equal to p + 20 bmax “p +12.5 f) where p = specific bearing load [N / mm] b) the remaining web width (s) in Qim] equal to or greater preferably equal to 525 (p + 20) -7- 1 plain bearing element with inhomogeneous anti-friction layer, consisting of a support layer and one on the AT 392 522 B plain bearing material filled recesses in the Tiagschicht, characterized in that the groove width (b) of the recesses, the web width (s) remaining between the recesses and the ratio of groove width (b) to web width (s) for lightly resilient base layers, d . H. Base layers with a load capacity below approximately 35 N / mm 1 2, based on the projected bearing surface, are coordinated in the following manner: a) Width (b) of the groove-like depressions [μm] equal or greater, preferably equal to p + 20 ^ min ”56 , 25 p + 12.5 b) remaining web width (s) in [pm] equal or less, preferably equal to 2050 (p + 20) smax = “118.06 + 0.652. p + 6.528. IO’2. p2 + 3,889.10,3. p3 c) the ratio of groove width (b) to remaining web width (s) (b / s) min * (0.5 to 0.55). (0.5100 + 0.9. IO'3. P + 2.1. IO * 4. P2). 3. plain bearing element with an inhomogeneous anti-functional layer, consisting of a support layer and a support layer made of bearing material applied to the support layer, which, with an essentially axial spacing from one another, is arranged essentially in parallel and is distributed at least over part of the sliding surface and is filled with groove-like depressions filled with a plain bearing material , wherein the bearing material of the base layer has a lower or greater hardness than the slide bearing material filling the recesses, for example radial slide bearings with recesses in the base layer which extend in the circumferential direction at an axial distance from one another and are filled with slide bearing material, characterized in that the groove width (b) of the recesses , the web width (s) remaining between the depressions and the ratio of the groove width (b) to the web width (s) for medium-strength base layers, d. H. Base layers with a load capacity of between approximately 30 and approximately 55 N / mm, based on the projected bearing surface, are coordinated as follows: a) Width (b) in [pm] of the groove-like depressions is smaller or larger, preferably equal to p + 20 p + 12 , 5 b) the remaining web width (s) in [pm] less or greater, preferably equal to 750 (p + 20) -8-1 smit = 118.06 + 9.652. p + 6.528.10’2. p2 + 3,889.10,3. p3 2 c) the ratio of groove width (b) to remaining web width (s) 3 (b / s) with = 0.9444 + 1.6667.10 * 3. p + 3.8889.10 * 4. p2 4 plain bearing element according to one of claims 1 to 3, characterized by the coordination of the groove depth (t) in [pm] of the groove-like depressions and the ratio of the groove width (b) to the groove depth (t) of the groove-like depressions for heavy-duty slide bearing materials filling the depressions , d. H. Plain bearing materials with a load capacity above about 40 N / mm2, based on the projected bearing surface, in the following way: d) Groove depth in [pm] equal or less, preferably equal to 1350 tmax = p +12.5 AT 392 522 B and e) das Ratio of groove width (b) to groove depth (t) of the groove-like depressions (b / t) min = 4.167. IO * 2. p + 0.8333. 5. plain bearing element according to one of claims 1 to 3, characterized by the coordination of the groove depth in [pm] of the groove-like depressions and the ratio of the groove width (b) to the groove depth (t) of the groove-like depressions for low-load, the groove-like depressions filling slide bearing materials, d . H. Plain bearing materials with a load capacity below about 25 N / mm2, based on the projected bearing surface, in the following way: d) Groove depth in [pm] equal to or greater, preferably equal to 900 tmin88 p + 12.5 and e) the ratio of groove width (b ) to groove depth (t) of the depressions (b / t) max = i1'95 to 2> °)) (10> 834 * 10'2 * P + 2.1666). 6. plain bearing element according to one of claims 1 to 3, characterized by the coordination of the groove depth (t) in [pm] of the groove-like depressions and the ratio of the groove width (b) to Nutdefe (t) of the groove-like depressions for medium-duty, filling the groove-like depressions Plain bearing materials, < L h. Plain bearing materials with a load capacity between approximately 20 and approximately 45 N / mm2, based on the projected bearing surface, in the following manner: d) Groove depth (t) in the [pm] of the recesses less or greater, preferably equal to 1125 W = p + 12.5 and e) the ratio of the groove width (b) to the groove depth (t) of the depressions: (b / Omit = 6,667. IO * 2. p + 1,333. In addition 4 sheets of drawings -9-