KR19990082076A - Plain bearing prosecution with pockets for lubricant - Google Patents

Abstract

A plain bearing element is described which comprises at least one single layer metal bearing material 4 and on which sliding surface 6 the lubricant pockets 6 are made. Length T of the open oil pockets 10. Is 0.03 mm to 0.3 mm, and the ratio of pocket area to pocket depth is 10 to 40 mm. The running characteristics of these bearing elements are better than those of known plain bearing elements with oil pockets and their properties are better than those of known bearings with both open and filled grooves. The depth of the oil pockets 10 may preferably be adapted to the viscosity of use of the lubricating oil. The oil pockets 10 in the same plain bearing piece may also have a different depth T and are formed only in predetermined areas of the plain bearing piece.

Description

Plain bearing prosecution with pockets for lubricant

The formation of settlements on sliding surfaces has been known for many years. It is proposed in DE-PS 546 781 to make discontinuities, settlements, roughness and similar means on one of the contact surfaces of the bearing to avoid "contact oxidation". Circular sinks were also seen in this relationship, but this does not describe what dimensions these sinks have and how they are arranged or embedded.

DE-OS 834 480 describes a bearing whose bearing surface consists of a number of small sections made of hard and soft bearing material. In addition to the grooved settlements, also grooves in the shape of rectangles are formed but these are completely filled with a soft bearing material. Settlements are made by embossing spinning in a metal bath.

From DE-PS 27 11 983, in addition to the oil grooves, also hemispherical oil grooves of 1.5 to 2.5 mm diameter arranged with a 4 mm gap in the circumferential direction or a 4.8 mm gap in the axial direction. Bearings are known. Since the bearing alloy is only 0.25 mm thick, these oil grooves extend to the backing of the steel. Lubricant pockets of this size have disadvantages, among other things, that the joining zone of the bearing alloy with the steel backing is exposed so that disassembly can occur in this area.

From DE 33 26 316 C2 bearing bushes of sintered metal with lubricating oil pockets arranged on the inner sliding surface are known. The oil pockets are 0.2 to 1 mm thick while 10 to 30% of the total sliding surface is occupied by the oil pockets.

AU 143 992 shows a sliding surface design with embossed grooves filled as a soft plain bearing material as a whole.

DE-GM 7817118 describes self-lubricating bearings having pupils of circular or spherical shape for embedding solid lubricants.

From US 5 462 362 a sliding element is known which is used for extremely low sliding speeds as a spherical element in artificial joints. This sliding surface has cylindrical grooves having a diameter of 0.2 to 0.8 mm and a depth of 1 to 10 mu m. These grooves are also filled with solid lubricants.

The present invention relates to plain bearing mechanisms comprising single or multiple layers of metal bearing materials, in which pockets for lubricating oil are formed in sliding surfaces. The term "plane bearing prosecution" is intended to mean, among other things, plain bearing half liners, flange bearings, bushes and thrust washers, which comprise a single or multiple layers of metal bearing materials which can be deposited on the backing material. .

1 is a perspective view of a plain bearing half-liners according to a first embodiment,

2 is a perspective view of a bearing bush,

3 is a cross-sectional view taken along line III-III in the plain bearing half-liner shown in FIG.

4A and B are cross-sectional views taken along the line VII-VII of the plain bearing half-liner shown in FIG. 1 for two phase transfer embodiments;

5 is a perspective view of a plain bearing according to another embodiment,

FIG. 6A is a cross-sectional view taken along line VII-VII in the plain bearing half-liner shown in FIG. 5,

FIG. 6B is a cross sectional view taken along line VIIb-VIIb in the plain bearing half-liner shown in FIG.

7A, B are plan views of the developed sliding surface of the plain bearing half-liner shown in FIG. 1 for two different embodiments,

8 is a perspective view of a flanged bearing,

9 is a figure which is the rotational speed drawn in case of inadequate lubrication, and

10 is a diagram for the sliding behavior.

Therefore, the running quality of the sliding elements is better than the techniques of known plain bearing elements with oil pockets and their properties are better than the properties of both bearings with open and filled grooves and bearings without oil pockets. It is an object of this invention to improve sliding indictments having a lubricant pocket to an extent.

The above object is achieved by a plain bearing element having the features of claim 1. Advantageous embodiments are the subject of the dependent claims.

Many experiments with lubricating pockets of various shapes known from the prior art have not resulted in significant improvements in the performance of the operation and, consequently, cannot benefit from the choice of size. Since oil pockets generally reduce the proportion of supporting surfaces, oil pockets must be regarded as a disadvantage as a result.

Therefore, plain bearing devices whose oil pockets have a small depth of 0.03 mm to 0.3 mm and a ratio of pocket width to pocket depth of 10-40 mm are for example internal combustion when using conventional lubricants such as engine oil according to SAE. It was even more surprising to show remarkable performance in use under common operating conditions for the main and big-end bearings of the engine. Lubricant pockets are fully filled with lubricant only when these sizes are observed, and as a result, during operation, the hydrodynamic pressure is in sliding contact with respect to the narrowly bound pockets that are closed on all sides except the sliding surface. This pressure is obviously the same as on a smooth sliding surface and consequently provides a surprising contribution to the ratio in supporting work.

At any time this pocket depth must be less than the thickness of the layer of bearing material from which the oil pockets are made.

The above sizing of the oil pockets is preferably applied to bearing elements having a diameter of 35 to 160 mm. The depths of the oil pockets are preferably in the order of magnitude of the play between the charges in sliding contact.

The load is received not only by the support surface between the oil pockets but also by the lubricant in the oil pockets, as a result of which the oil pockets are not used only for the supply of lubricants as in the prior art. As a result, sliding speeds greater than 20 m / sec and a load of 50 MPa or more can be used for aluminum alloys and can be used without any problem of 70 MPa for bronze with electroplated layers. Even when the support surfaces run dry, the anti-ageise property is also improved because the lubricant in the pockets contributes to hydraulic support. In addition, friction losses are clearly reduced.

Compared to bearings with open grooves (US 45 38 929), which are also not filled with soft bearing material (US 45 38 929), the plain bearing elements according to the invention cannot rise in the circumferential direction as in the case of grooves where the lubricant in the oil pockets does not. However, it accumulates in oil pockets and the inflow and outflow of lubricant is better by only passing through a thin lubrication gap. In addition to the hydraulic pressure, the pressure component is also developed due to the diffuser action into the oil pocket when the lubricant is introduced, while the pressure component is produced by the damming-up edge at the outflow. .

The properties of the plain bearing elements can be further optimized when considering the relationship between the sizing of the oil pockets and the viscosity of the lubricants used. The oil pockets in bearings for internal combustion engines should preferably be T = 0.5 T = e ^a , where T at the operating temperature is given as a = 0.45-1n n-3 mm when the dynamic viscosity n of the lubricant is given in mMPa to be. The bisector is applied to a working viscosity of y = 1.8 mPa to 50 mMP, corresponding to the use of conventional engine oils in fields of about 60 ° to 180 ° (OR Lang, W. Steinhilper "Gleitlager", 1978, Springer- Verlag, P 36).

All areas of the oil pockets should preferably not exceed 10% of the total area of the sliding surface of the plain bearing element, since otherwise the ratio of the area of the uninterrupted support surface to withstand high loads in modern internal combustion engines Is too small.

All oil pockets do not necessarily have the same depth. Conversely, in order to improve the supply of lubricant and to continuously reduce the depth of the oil pockets towards the area where the thickness of the lubricating film is increasing, the depth of the oil pockets in the area of the minimum thickness or highest load of the lubricating film is selected. May be recommended for specific uses. Especially. In the case of big-end bearings and main bearings, these areas of exposure to the highest loads and the most dangerous due to abrasion are known, and as a result a plain bearing mechanism can be provided.

In case of inadequate lubrication, the opposite can also be advantageous. That is, deeper oil pockets are arranged in the unloaded zones thereby providing additional oil storage.

The oil pockets are preferably embossed in the bearing material. Machining is preferably carried out in a strip state. This is much easier than making grooves in an already molded bearing liner. After embossing the oil pockets, the strip-shaped material is deformed and finally processed into sliding surfaces.

Bearing materials in which oil pockets are made therein to obtain good loadability are preferably relatively hard alloys based on aluminum or copper. Such bearing materials can be exposed to high loads and they have the advantage of being directly welded onto the steel backing. Due to the relatively high tendency of the pressing of such rigid bearing materials these materials could only be used for low sliding speeds without further plating. In order to cope with the tendency to sticking, tests have been conducted in the past to add more tin or lead to these alloys in addition to additional coatings. It has been found that by the installation of oil pockets according to the invention the addition of the soft materials described above can be largely eliminated. It has also been found that plain bearing elements with these bearing alloys can be used not only for higher sliding speeds but also for high loads. In addition, the material's ability to prevent sticking was also significantly improved by the special design of the oil pockets. According to a further embodiment the sliding surface of the bearing material from which the pockets are made is coated with an additional electroplated layer or with a sputtered layer whose thickness is much smaller than the thickness of the oil pockets. It can be made on any bearing materials of such a coating, but can preferably be made on lead bronze.

The oil pockets are preferably not completely filled with the electroplated layer or the sputtered layer. On the contrary, the sinks are maintained on the sliding surface. Since the electroplated or sputtered layers form a continuous coating, a continuous coating is obtained between the support surface and the zones of the oil pockets regardless of the shape of the oil pockets. The worn parts of the edge injury of the oil pockets, which could have been caused by embossing of the bearing material or by cutting of the sliding surface, are smoothed by a coated and electroplated layer or sputtered layer.

The thickness of the electroplated or sputtered layer may be greater than the depth T when the oil pockets are assured that the contour of the electroplated or sputtered layer follows the contour of the oil pocket made from the layer of bearing metal.

For example, the following bearing alloys can be used:

AlNi2MnCu, AlZn5SiCuPbMg, AlSn6, CuPb22Sn, CuPb17Sn5, CuPb10Sn10 or CuPb22Sn3, Preferred electroplated layers are PbSn 10 Cu2, PbSn 10 Cu. The sputtered layer is AlSn2O.

Any type of oil pockets can be chosen; However, oil pockets have been found to be advantageous when the spherical fragments have the shape of a truncated cone. The side wall angle of the cone shaped oil pockets should be in the range between 30 ° and 60 °, preferably at 45 °. The inclination of the sides can be used to adjust the proportion of lubricant forced by the movement of the elements in sliding contact from the oil pockets onto the support surface portion. The advantage of the oil pockets is that pressure is also generated in the region of the oil pockets, so the purpose is to transport as little lubricant out of the oil pockets as possible during operation under high loads. On the other hand, larger angles are preferred if the purpose is to improve the properties that prevent the first press. As a result, smaller angles from the range of 30 ° to 60 ° are preferred for the sidewall angle ∝.

According to another embodiment the oil pockets may have rhombus shapes in plan view.

The plain bearing element is preferably a plain bearing half-liner. In embodiments the oil pockets are preferably arranged in sequence with lines transverse to the circumferential direction and the surrounding lines make an angle β, preferably between 15 ° and 40 °, with respect to the direction. This linear arrangement roughly corresponds to the arrangement of the grooves in the grooved bearing but the angle β is larger.

The oil pockets are arranged one after the other in a straight line and they are also preferably transverse to the axial direction and the transverse lines make an angle between the axial direction of the bearing liner and an angle r preferably between 5 ° and 25 °. Because of the angles β and α, the longitudinal and transverse lines form a rhombus model.

The above arrangement of oil pockets is more advantageous because otherwise a shadow effect is produced which does not contribute to the improvement of the running quality of the plain bearing liner if all the oil pockets are arranged in close order, and vice versa. It was found that you can have even.

The subsequent arrangement of oil pockets is not disadvantageous if the spacing of adjacent oil pockets in the direction of sliding, ie in the circumferential direction in the case of liner and bush, is at least 12 mm.

Depending on the purpose of use, the oil pockets may be confined to the crown area and to the area of the plain bearing liner or bushing angle δ of ± 30 ° to ± 60 ° around the area.

The plain bearing elements according to the invention are particularly suitable for main and big-end bearings for piston engines, in particular for internal combustion engines, as that is not the case with conventional sliding elements with open sinks.

Embodiments of the present invention will now be described in more detail with reference to the drawings by way of example.

Fig. 1 shows in a perspective view plain bearing hard-liners where the plain bearing half-liners bear on top of each other at their dividing line surface 9 and for example form a main or big-end bearing. And in Fig. 2 the bearing bush 2 is shown in perspective view. On both sides of the steel backings 3, for example aluminum alloys 4 and 4 'are deposited.

Caps forming lube pockets 10, 10 'in the surface of the aluminum alloy forming the sliding surfaces 6, 6' of the plain bearing half-liner 1 or of the bearing bush 2 Shaped settlings are embossed. In the embodiments shown in FIGS. 1 and 2, the oil pockets 10, 10 ′ are uniform over the entire sliding surface 6, 6 ′ of the plain bearing half-liner 1 or bearing bush 2. Is distributed.

FIG. 3 shows the short-lives along the line III-III through the half-liner shown in FIG. 1. As can be seen it has the shape of a spherical segment of oil pockets 10 and its diameter D is much larger than the depth T of oil pockets 10 measured from the sliding surface 6 (see also FIG. 6A). ). Oil pockets 10 are entirely contained within each plain bearing material. That is, T is smaller than the thickness of the aluminum layer 4. The diameter D of the oil pockets 10 may be in a spherical wall of about 0.5 mm to 3.5 mm, while such diameters and depth values may be combined such that the ratio of pocket area to pocket depth is 10 to 40 mm. . For example, any geometrical shape is possible in principle, as shown in FIG. 7B. The arrangement of the oil pockets 10 'of the bearing bush 2 corresponds to those shown in FIG.

4A and B show cross-sectional views taken along line IV-IV of the plain bearing half-liner shown in FIG. 1 for two embodiments. Oil pockets are of different depths; The depth in the embodiment shown in FIG. 4A is continuously decreasing from the crown zone 8 to the dividing line surfaces 9. The oil pockets 10a in the region of the dividing line surfaces have a depth that is only half of the oil pockets 10c in the region of the crown region 8 of the plain bearing half-liner 1. The oil pockets 10b in the intermediate carryover region, on the contrary, have a depth lying approximately between the oil pockets 10c and the oil pockets 10a. The IV-IV cross-sectional view of FIG. 4B shows oil pockets 10a ', 10b', 10c 'in which the depths of the oil pockets are in opposite arrangements as compared to FIG. 4A. As is apparent, the oil pockets 10c 'in the crown region 8 have the smallest depth in the crown region 8, while the depths of the oil pockets 10b' and 10a 'are separated by the dividing line surfaces ( 9) to increase.

The arrangement or shape of oil pockets 10a, b, c or 10a ', b', c 'can be transferred to the bearing bearing bush 2 in FIG.

In Fig. 5 another embodiment of a plain bearing half-liner 1 is shown in which oil pockets 10 "are installed only in the region of the crown region 8 in the region of ambient angle δ = ± 45 °. It is the area of the maximum load of the bearing or the area of the smallest thickness of the lubricating film The design of the plain bearing half-liner 1 in Fig. 5 is that the lead bronze 4a is first deposited on the steel backing 3. And the former differs from the design in FIG. 1 by being entirely coated with an electroplated layer 5 or a sputtered layer.

FIG. 6A shows the oil pockets 10 in the form of spherical segments in section VIa-VIa of the plain bearing half-liner 1 according to FIG. 1.

FIG. 6B is a section VIb-VIb with a plane half-liner 1 in accordance with FIG. 5, showing the cone shaped oil pockets 10 ″, the side walls 11 of which are angled at about 45 ° with the vertical line. The oil pockets 10 "are embossed in the lead bronze 4a and the electroplated layer 5 has the same thickness d anywhere even in the region of the oil pockets. The oil pockets 10 " are therefore totally embedded but have the same depth as they had before their electroplating operation, while the thickness d of the electroplated layer 5 is embossed oil pockets on the lead bronze 4a. It is smaller than the depth T of the fields 10 ", but this need not be the case in principle. Oil pockets must be guaranteed to be open to receive lubricant as before.

FIG. 7A is a plan view of the developed sliding surface 6 of the plain bearing half-liner 1 shown in FIG. 1. The oil pockets 10 are in turn arranged in longitudinal lines 15 and the longitudinal lines 15 make an angle β about 30 ° from the circumferential direction 17. The oil pockets are also arranged in transverse lines 16 which make an angle δ with an axial direction 18 and 15 °. This angular arrangement ensures that the oil pockets space apart at least 12 mm in the circumferential direction 17.

FIG. 7B shows an exploded view of the sliding surface 6 having oil pockets 10 that are rhombic in plan view in a similar manner to FIG. 7A.

8 shows a perspective view of the flange bearing 19. As is apparent, the flanges 20 are also provided with lubricating oil pockets 21 and the arrangement and shape of the oil pockets 21 are comparable to the oil pockets described above.

9 and 10 show comparative tests.

9 shows the maximum rotational speed resulting in maximum compression in the case of both plain bearings with and without oil pockets in case of inadequate lubrication. Bearing liners of steel with lead alloys of lead bronze with electroplating grades were tested. Bearing liners with oil pockets had the following specifications;

Pocket Depth: 0.08mm

Ratio of pocket face to pocket depth: 22 mm

Total area of all oil pockets: 45 mm2-3% of total sliding surface

B: 21 °

δ: 10 °

In this test the oil pockets were evenly distributed over the entire sliding surface and all oil pockets had the same depth (T). The viscosity of the lubricating oil was y = 3mMPa.

The figure in FIG. 9 shows that in the case of inadequate lubrication the bearing according to the invention can be rotated at a higher rotational speed before pressing occurs.

The stick figure in FIG. 10 shows the sliding behavior of steel bearing liners with a plated layer of aluminum alloy based on 15 tests with plain bearing layers without oil pockets. Pressing in all bearing liners occurred after a maximum of 10 hours. With plain bearing liners of the same alloy but with oil pockets were also performed at increased speed in 10 tests, of which 9 tests lasted 200 hours and one test lasted more than 500 hours. All tests were stopped at test time without damage. The shape of the oil pockets was the same as in the test according to FIG. 9.

The above known bearing elements can be used only for low sliding speeds up to about 5 m / sec and for average loads up to about 30 MPa, depending on the bearing material. These bearing elements are due to the large area occupied by the oil pockets and / or the relatively large depths, and therefore the configuration of the hydrodynamic pressures required for these uses is not possible to this extent.

Bearing elements according to EP-PS 104159 and US Pat. No. 5,238,311, which have grooves in the shape of a sliding surface having a sliding surface depth of 3 to 6 탆, are also known. These prosecutions may cause plastic deformation or wear and cause crushing when the grooves are subjected to loads of 30 MPa or more common in the big-end bearings and main bearings of internal combustion engines, and they no longer perform their work. Can not.

The groove bearings described in EP-PS 57 808, which include grooves filled with soft bearing materials, are in practice the soft bearing material is washed off by lubricating oil after a certain period of operation and the bearings can no longer function.

Claims (20)

In a plain bearing mechanism comprising at least one single or multiple layers of metal bearing material, the pockets for lubricating oil being formed on a sliding surface, The depths T of the oil pockets 10, 10 ', 10 ", 10'", 10a, b, c measured by the surface of the plain bearing element are 0.03 mm to 0.3 mm while the pocket width relative to the pocket depth Plain bearing prosecution characterized in that the ratio is 10 to 40 mm. The method of claim 1, For lubricants having a service viscosity n of 1.8 to 50 mMPa, the depth T (in mm) of the oil pockets 10, 10 ', 10 ", 10"', 10a, b, c is in the range of T = 0.5 to 1e ^a Plain bearing prosecution, characterized in that a = 0.45 · 1n n-3. The method according to claim 1 or 2, Plain bearing prosecution characterized in that the area of all oil pockets (10, 10 ', 10 ", 10"', 10a, b, c) is at most 10% of the total sliding surface (6, 6 '). According to one of claims 1 to 3, Plain bearing prosecution characterized in that the oil pockets (10, 10 ', 10 ", 10"', 10a, b, c) have different depths (T). The method of claim 4, wherein The oil pockets 10a, b, c have the greatest depth in the region of the highest or minimum thickness of the lubricating film and the above depths are continuously reduced towards areas of less load or increasing thickness of the lubricating film. Plain bearing prosecution. The method of claim 4, wherein The oil pockets (10a ', b', c ') in the zone of least load have a maximum depth and the thicknesses decrease continuously towards the zones of larger load. The word of claim 1 to claim 6, wherein Plain bearing indictment, characterized in that the oil pockets (10, 10 ', 10 ", 10"', 10a, b, c) are embossed. The method according to any one of claims 1 to 7, Plain bearing indictment, characterized in that the bearing material is an aluminum alloy (4, 4 ') in which oil pockets (10, 10', 10 ", 10" ', 10a, b, c) are made. The method according to any one of claims 1 to 8, The sliding surfaces 6, 6 ′ comprising oil pockets 10, 10 ′, 10 ″, 10 ″ ′, 10 a, b, c are coated with an electroplated layer 5 or a sputtered layer. Plain bearing prosecution. The method of claim 9, The thickness d of the electroplated layer 5 or sputtered layer is characterized by being smaller than the depth T of the oil pockets 10, 10 ′, 10 ″, 10 ″ ′, 10a, b, c made therein. Plain bearing prosecution. The method of claim 9, The thickness of the electroplated layer 5 or sputtered layer is greater than the depth T of the oil pockets 10, 10 ′, 10 ″, 10 ″ ′, 10a, b, c and the electroplated layer 5 Or the plane of the sputtered layer 5 is characterized in that it follows the contours of oil pockets etc. (10, 10 ', 10 ", 10"', 10a, b, c) made in the bearing metal layer. The method according to any one of claims 1 to 11, Plain bearing indictment, characterized in that the oil pockets (10, 10a, b, c) have the shape of spherical fragments. The method according to any one of claims 1 to 11, The oil pockets 10 " are plain cone propelled. The method of claim 13, A plain bearing prosecution characterized in that the side wall angle ∝ of the conical oil pockets 10 " is between 30 ° and 60 °. The method according to any one of claims 1 to 11, Plain bearing indictment, characterized in that the oil pockets (10 "') in the plan view have a rhombus shape. In a plain bearing liner or a plain bearing prosecution according to any one of claims 1 to 15, The oil pockets 10, 10 ′, 10 ″, 10 ″ ′, 10a, b, c are in turn arranged in longitudinal lines 15 and the heterogeneous lines 15 are in the circumferential direction 17. A plain bearing prosecution characterized by making an angle β between 15 ° and 40 °. The method of claim 16, The oil pockets 10, 10 ', 10 ", 10"', 10a, b, c are in turn arranged in transverse lines 16 which make an angle δ between the axial direction 18 and 5 ° and 25 °. Plain bearing prosecution characterized in that. The word of claim 1 to claim 17, wherein The oil pockets 10a, b, c are arranged in longitudinal lines 15 and transverse lines 16 and adjacent oil pockets 10, 10 ', 10 ", 10"', 10a in the sliding direction. Plain bearing prosecution, characterized in that the spacing of b, c) is at least 12 mm. The word of claim 16, wherein The oil pockets 10, 10 ', 10 ", 10"', 10a, b, c are characterized in that they are arranged in a range of ambient angles of ± 30 ° to ± 60 ° around the crown section 8 Plain bearing prosecution. Use of the plain bearing components according to any of claims 1 to 19 as main bearings and / or big-end bearings in piston engines, in particular internal combustion engines.