DE102006010698B4 - Bearing shell and bearing - Google Patents

Abstract

Bearing shell (1), in particular for crankshaft bearings, with partial surfaces (2, 3) lying orthogonal to the circumferential direction in a common plane, with an oil groove (10) extending at least partially over the circumference on the inner sliding surface (4) and with at least one in the oil groove (10) opening oil bore (5), the oil groove (10) opening into the second partial surface (3) and ending with its groove end (12a) at a distance from the first partial surface (2), characterized in that the groove cross-sectional area to the groove end (12a) is continuously reduced, and that the groove cross-sectional area decreases from the apex (6) of the bearing shell (1) at least in the direction of the second partial surface (3).

Description

The invention relates to a bearing shell, in particular for crankshaft bearings with partial surfaces, lying with orthogonal to the circumferential direction in a common plane faces, with an on the inner sliding surface at least partially extending over the circumference oil groove, and with at least one opening into the oil groove oil hole, said Oil groove opens into the second part surface and ends with its groove end at a distance from the first part surface. The invention also relates to a bearing with such a bearing shell.

From the EP 1 510 709 A2 is known a bearing shell with an oil groove, the first groove portion with a constant large groove cross-section passes before each of the two faces in the second groove sections, the cross-sections are continuously reduced in the direction of the face.

This continuously decreasing cross-sectional area, due to the rotation of the counter-rotor at one face, results in a pressure jam which leads to an improved forced supply of the connecting rod bearing shells, which are supplied via bores in the crankshaft starting from the main journals. This side of the bearing shell is called the overpressure side.

In addition, the reduction of the Ölnutquerschnittes offers the further advantage that the oil pump power can be reduced, whereby the power loss of the internal combustion engine is reduced.

Due to the rotation of the counter-rotor, however, a negative pressure simultaneously arises at the other partial surface, which has the disadvantage that, in spite of the reduction in cross-section, an oil-pressure loss is caused on this side of the partial surface. This side of the bearing shell is called the negative pressure side.

The oil pressure loss on the negative pressure side is due to the fact that the applied pump pressure P _{P is} greater than the negative pressure P _rotation generated by the rotation of the counter-rotor (crankshaft) (P _pump > P _rotation ). The oil pressure loss is caused by the fact that the oil can easily escape laterally beyond the groove cross-section and the wall thickness course (free-puller or exposure area) of the bearing shell, which possibly reduces towards the partial surface.

This circumstance is deliberately accepted on the overpressure side (P _pump + P _rotation ), because in the application it must be ensured that any dirt present in the engine can be flushed out over the partial surface.

The JP 8-93769 A describes a bearing shell with a groove which extends only over a portion of the inner circumference. At the end of the groove, which ends at a distance to a partial surface, a step is provided, against which the supplied oil flows and generates a dynamic pressure there. Before the step, an outlet opening is provided in the groove, through which the accumulated oil can be removed. By means of a control device in the outlet line of the dynamic pressure can be adjusted and matched to the game of the counter-rotor with the bearing shell. This bearing shell or a bearing formed therefrom has the disadvantage that the primary dirt accumulates before this stage and can only be dissipated to a limited extent via the outlet line.

The EP 1 557 544 A1 discloses a symmetrical bearing shell in which the oil groove ends at a distance to both the first and the second part surface.

The US 2,631,905 A discloses in the sliding surface oil pockets, the extent of which is smaller in the circumferential direction than in the transverse direction.

The DE 1 576 354 A describes basic bearings in internal combustion engines, which either show a groove that ends before the apex of the bearing shell or in the direction of the second Teilfäche has a constant cross-sectional area.

The object of the invention is therefore to provide a bearing shell, in which the resulting on the negative pressure oil pressure loss is reduced.

This object is achieved with a bearing shell with the features of claim 1 and with a bearing with the features of claim 18.

It is envisaged that the groove cross-sectional area decreases from the vertex of the bearing shell at least in the direction of the second partial area, preferably in both directions, ie in the direction of the first partial area and in the direction of the second partial area. This can be realized by reducing the groove width B and / or the groove depth T. Preferably, the groove depth of T ₁ , measured at the apex of the bearing shell, is reduced to T ₂ = 0.1 · T ₁ , where T ₂ denotes the groove depth at the second partial surface.

According to a further embodiment, the oil groove has a first section with a large groove cross-sectional area and a second section with a small groove cross-sectional area, wherein the first section with a large groove cross-sectional area terminates at a distance from the first partial area and the second section with a small cross-sectional groove area ends at the one side into the second partial area and at the other in the first section opens.

The asymmetrical configuration of the oil groove causes a corresponding installation position of this bearing shell with respect to the direction of rotation of the counter-rotor or with respect to the flow direction of the oil. The bearing shell is to be installed in such a way that the lubricating oil flows from the first partial surface to the second partial surface. At the end of the flow path, the oil groove is open to the second partial surface.

The bearing shell whose oil groove has a portion of lesser cross-section is to be installed such that the portion of the oil groove having the smaller cross-sectional area is located at the end of the flow path of the oil. This means that the portion of the oil groove having a smaller cross-sectional area forms the overpressure side and the portion of the oil groove having the larger cross-sectional area forms the negative pressure side. The advantage of this bearing shell is that there is no or at most significantly lower oil loss on the negative pressure side because of the larger in comparison with the prior art groove cross-sectional area. The improved oil pressure conditions also lead to an improved supply of the connecting rod bearings.

Preferably, the groove depth T _{1 of} the first section is greater than the groove depth T _{2 of} the second section.

The groove depth T _{1 of} the first section, measured at the vertex of the bearing shell, is preferably 1.6 mm to 2.4 mm, in particular 1.8 mm to 2.2 mm.

The groove depth T _{2 of} the second section, measured on the partial surface, is preferably in the range from 0.2 mm to 1 mm, in particular from 0.4 mm to 0.8 mm.

In order to realize different cross-sectional areas of the first section and the second section, the groove widths can be correspondingly chosen differently, and this can also be combined with the groove depths.

Preferably, the groove width B _{1 of} the first portion at the apex is greater than the groove width B _{2 of} the second portion measured at the partial surface. Slot width B ₁ Groove width B ₂ 1,5-2,0 mm 1.0 mm 2,0-2,5 mm 1.0-1.5 mm 2.5-3.0 mm 1,5-2,0 mm 3.0-4.0 mm 1,5-2,5 mm 4,0-6,0 mm 2,0-3,5 mm

Preferably, the groove width B _{2 of} the second section is at least 0.5 mm smaller than that of the first section.

Irrespective of the groove width and groove depth, the ratio of the groove cross-sectional area F ₁ in the first section to the groove cross-sectional area F ₂ in the second section is preferably 5 to 30, in particular 10 to 20.

The groove cross-sectional area of the second section can be constant over the respective groove length.

In order to prevent sudden pressure changes of the oil in the oil groove, the groove cross-sectional area of the first portion in the apex of the bearing shell is preferably greatest and decreases continuously to the groove ends.

As a particular embodiment, the circular arc forming the groove base as the first section has a radius of curvature R ₁ which is smaller than the radius of curvature R of the circular arc forming the sliding surface. The centers of the circular arcs are offset, wherein the center of the groove bottom forming arc is offset to the bearing shell out.

The groove cross-sectional area of the second section can also change continuously. Preferably, the groove cross-sectional area of the second portion continuously decreases from the second partial surface toward the first portion.

In order to facilitate the passage from the first to the second section, the second section with a small groove cross-sectional area preferably extends partially into the first section with a large groove cross-section. Here, the second section extends with about ¼ to 1/3 of its length in the first section.

Preferably, the second section extends over an angular range α of 5 ° to 45 °, where α is calculated from the second partial surface. Further preferred angular ranges are 5 ° to 30 ° and 5 ° to 25 °. The shorter the angular range α is selected, the further the first section extends in the direction of the second partial surface. This also means that the negative pressure region is displaced to the second partial surface.

The oil groove or the first section preferably ends in an angular range β of 5 ° to 40 ° in front of the first partial surface. Preferred values are 5 ° to 30 ° and 5 ° to 20 °.

The bearing shell can additionally have an exposure area on both partial surfaces. In this case, it is preferably to be ensured that the exposure areas each end at a distance in front of the oil groove or before the first section.

The bearing shells according to the invention are preferably combined with a smooth shell to form a bearing. In such a bearing, a rotating counter runner is lubricated with oil. Since the bearing shell according to the invention is not symmetrical, pay attention to the mounting position. In this case, the bearing shell according to the invention is installed such that the lubricating oil flows from the first part surface to the second part surface or the second part is arranged in the flow direction of the oil behind the first part. This means that the second section is arranged on the overpressure side of the bearing shell.

Preferably, such bearings are used as crankshaft main bearings. In such crankshaft main bearings, the smooth shell forms the lower shell and the bearing shell according to the invention the upper shell.

Said ranges of values for the dimensions of groove width, groove depth and groove cross-sectional areas as well as for the angles α and β preferably apply to bearing shells with an inner diameter of 26 mm to 150 mm. Preferred inner diameters are 50 mm to 100 mm.

Exemplary embodiments of the invention are explained below with reference to the drawings.

Show it:

1a , b + c bearing shells in perspective view according to three embodiments,

2 the two ends of the in 1a shown bearing shell in a perspective view broken into two parts, for full insight into the two end portions in front of the faces,

3 a section through the in 1a shown bearing shell along the line III-III,

4 a section through the in 1a shown bearing shell along the line IV-IV,

5 an enlarged view of the detail X in 4 and

6 a bearing consisting of a bearing shell according to the invention and a smooth bearing shell.

In the 1a is a bearing cup 1 shown in perspective. The flow direction of the lubricating oil with rotating counter-rotor (in 1a not shown; in 6 reference numeral 9 ) is by the arrow indicated. The built-in bearing shell thus forms on the first part surface 2 the negative pressure side and at the partial surface 3 the overpressure side.

On the inner sliding surface 4 has the bearing shell 1 an oil groove 10 on, resulting in a first section 11 and a second section 15 divided. The first paragraph 11 has a large groove cross-sectional area and the second cross-section 15 a small groove cross-sectional area. The different groove cross-sectional areas are realized by different groove widths B ₁ and B ₂ .

In the oil groove 10 two oil wells open 5 through which the lubricating oil is supplied.

The second section 15 extends for about ¼ of its length into the first section 11 ,

In the 1b shown bearing shell differs from the in 1a shown bearing shell only in that before the two faces 2 and 3 each an exposure area 7 and 8th is arranged. These exposure areas 7 and 8th are achieved by a wall thickness reduction.

The 1c describes a bearing shell in which the oil groove 10 only one continuous section 11 has, the groove end 12a spaced to the partial area 2 is. The section 11 flows into the partial area 3 , The groove cross-sectional area is over the entire length of the oil groove 10 constant, ie B ₁ = B ₂ and T ₁ = T ₂ . The groove depth T ₂ , measured at the partial surface 3 , smaller T ₁ can also be chosen, where T ₂ = 0.1 · T ₁ (not shown).

Both bearing shells can consist of a solid material. But it is also possible to produce the bearing shell of a layer composite material, so that the bearing shell 1 For example, may have a steel backing and a bearing material with applied sliding layer.

In the 2 are the end sections of in 1a see bearing shell shown. The first paragraph 11 ends at a distance in front of the first partial surface 2 ,

If, as in 1b is shown below the partial surfaces 2 and 3 the exposure area 7 and 8th is present, lie the ends 12a . 12b the first section below and thus outside the exposure areas 7 and 8th ,

In the 3 is a section along the line III-III through the in 1a shown bearing shell shown. It can be seen that the groove cross-section of the first section is designed trapezoidal, wherein the groove width measured at the sliding layer side to the second partial surface 3 rejuvenated. The groove bottom 13 has a constant width.

The second section 15 also has a trapezoidal cross section, which in the direction of the partial surface 3 widened.

In the 4 is a section along the line IV-IV of in 1a shown bearing shell shown. The distance of the groove end 12a of the first section 11 from the first part surface 2 is characterized by the angle β. The length of the second section 15 the oil groove 10 is characterized by the angle α. Both angles have the value 20 ° in the embodiment shown here.

In addition, the radii of curvature R and R _{1 are located} . The radius of curvature R refers to the sliding surface 4 forming circular arc, while the radius of curvature R ₁ on the groove bottom 13 forming circular arc of the first section. It is clear to see that in the crown 6 the groove depth of the first section is the largest and continuously up to the groove ends 12a . 12b reduced. The centers of the radii of curvature R and R ₁ are correspondingly offset from one another.

In the 5 is an enlarged view of the detail X to see. It can be seen that the groove depth of the first section 11 in the direction of the second partial surface 3 reduced and in the second section 15 passes, the groove depth is the partial area 3 enlarged.

In the 6 a bearing is shown, which is used for example for a crankshaft main bearing. The bearing consists of a bearing shell according to the invention 1 , which is installed as a top shell. The lower shell is replaced by a smooth shell 100 formed, which has no oil groove. The counter-runner 9 , which symbolizes the crankshaft, rotates clockwise, allowing the oil to move between the counter-rotor 9 and the bearing shells 1 and 100 is flowing in the direction of the arrow.

LIST OF REFERENCE NUMBERS

1

bearing shell

2

first partial area

3

second subarea

4

sliding surface

5

oil well

6

vertex

7

exposure zone

8th

exposure zone

9

expeller

10

oil groove

11

first section with large groove cross-section

12a, b

groove end

13

groove base

15

second section with a small groove cross-section

100

Smooth bearing shell

B ₁

Width of the first section

B ₂

Width of the second section

T ₁

Depth of the first section

T ₂

Depth of the second section

F ₁

Cross-sectional area of the first section at the apex

F ₂

Cross-sectional area of the second section on the partial surface

α

angle

β

angle

Claims (19)

Bearing shell ( 1 ), in particular for crankshaft bearings, lying with orthogonal to the circumferential direction in a common plane faces ( 2 . 3 ), with one on the inner sliding surface ( 4 ) at least partially over the circumference extending oil groove ( 10 ) and at least one into the oil groove ( 10 ) opening oil well ( 5 ), wherein the oil groove ( 10 ) into the second partial area ( 3 ) and ends with its Nutende ( 12a ) at a distance to the first partial area ( 2 ), characterized in that the groove cross-sectional area to the groove end ( 12a ) and that the groove cross-sectional area of the vertex ( 6 ) of the bearing shell ( 1 ) at least in the direction of the second partial area ( 3 ) decreases. Bearing shell according to claim 1, characterized in that the groove width B from the vertex ( 6 ) of the bearing shell ( 1 ) at least to the second partial area ( 3 ) decreases continuously. Bearing shell according to claim 1 or 2, characterized in that the groove depth T from the vertex ( 6 ) of the bearing shell ( 1 ) at least to the second partial area ( 3 ) decreases continuously. Bearing shell according to claim 1, characterized in that the oil groove ( 10 ) a first section ( 11 ) with a large groove cross-sectional area and a second section ( 15 ) with a small groove cross-sectional area, that the first section ( 11 ) with a large groove cross-sectional area with the groove end ( 12a ) at a distance to the first partial area ( 2 ) and that the second section ( 15 ) with a small groove cross-sectional area on the one hand into the second partial area ( 3 ) and, on the other hand, in the first section ( 6 ) opens. Bearing shell according to claim 4, characterized in that in the first section ( 11 ) the groove depth T ₁ , measured at the vertex ( 6 ) of the bearing shell ( 1 ), is greater than the groove depth T ₂ in the second section ( 15 ), measured at the partial surface ( 3 ). Bearing shell according to claim 4 or 5, characterized in that in the first section ( 11 ) the groove width B ₁ , measured at the vertex ( 6 ) of the bearing shell ( 1 ), greater than the groove width B ₂ , measured at the partial surface ( 3 ), in the second section ( 15 ). Bearing shell according to one of claims 4 to 6, characterized in that the ratio of the groove cross-sectional area F ₁ in the first section ( 11 ) to the groove cross-sectional area F ₂ in the second section ( 15 )

where F _{1 is} the cross-sectional area in the vertex ( 6 ) of the bearing shell ( 1 ) and F _{2 is} the cross-sectional area at the second partial area ( 3 ) designated. Bearing shell according to one of claims 4 to 7, characterized in that the groove cross-sectional area of the second section ( 15 ) is constant over the respective groove length. Bearing shell according to one of claims 4 to 8, characterized in that the groove cross-sectional area of the first section ( 11 ) in the vertex ( 6 ) of the bearing shell ( 1 ) is greatest and is continuous with the groove ends ( 12a , b) reduced. Bearing shell according to claim 9, characterized in that the groove bottom ( 13 ) of the first section ( 11 ) forming circular arc has a radius of curvature R ₁ , which is smaller than the radius of curvature R of the sliding surface ( 4 ) forming circular arc. Bearing shell according to one of claims 4 to 10, characterized in that the groove cross-sectional area of the second section ( 15 ) from the second subarea ( 3 ) towards the first section ( 11 ) decreases continuously. Bearing shell according to one of claims 4 to 11, characterized in that the second section ( 15 ) with a small groove cross-section partially in the first section ( 11 ) extends with a large groove cross-sectional area. Bearing shell according to claim 12, characterized in that ¼ to 1/3 of the second section ( 15 ) in the first section ( 11 ). Bearing shell according to one of claims 4 to 13, characterized in that the second section ( 15 ) extends over an angular range α of 5 ° to 45 °, wherein α from the second partial surface ( 3 ) is calculated. Bearing shell according to one of claims 1 to 14, characterized in that the oil groove ( 10 ) in an angular range β of 5 ° to 40 ° in front of the first partial surface ( 2 ) ends. Bearing shell according to one of claims 1 to 15, characterized by two exposure areas ( 7 . 8th ) at the two partial surfaces ( 2 . 3 ). Bearing shell according to claim 16, characterized in that the exposure areas ( 7 . 8th ) in each case at a distance in front of the oil groove ( 10 ) or before the first section ( 11 ) of the oil groove ( 10 ) end up. Bearing, in particular crankshaft main bearing, with a bearing shell ( 1 ) having sub-surfaces orthogonal to the circumferential direction in a common plane ( 2 . 3 ), with one on the inner sliding surface ( 4 ) at least partially over the circumference extending oil groove ( 10 ) and with at least one opening in the oil groove ( 5 ), wherein the oil groove ( 10 ) into the second partial area ( 3 ) and ends with its Nutende ( 12a ) at a distance to the first partial area ( 2 ), wherein the groove cross-sectional area to the groove end ( 12a ) is continuously reduced and the groove cross-sectional area of the vertex ( 6 ) of the bearing shell ( 1 ) at least in the direction of the second partial area ( 3 ) and with a plain bearing shell ( 100 ), in which an oil-lubricated, rotating counter-rotor is storable, wherein the bearing shell ( 1 ) is installed such that the lubricating oil from the first partial surface ( 2 ) to the second partial area ( 3 ) flows. Bearing according to claim 18 with a bearing shell ( 1 ), in which the oil groove ( 10 ) a first section ( 11 ) with a large groove cross-sectional area and a second section ( 15 ) having a small groove cross-sectional area, the first section ( 11 ) with a large groove cross-sectional area at a distance from the first partial area ( 2 ) and the second section ( 15 ) with a small groove cross-sectional area on the one hand into the second partial area ( 3 ) and, on the other hand, in the first section ( 11 ) opens.

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