HYDRODYNAMIC SLIDE BEARING

Abstract

A hydrodynamic slide bearing (10, 10′) supports a shaft (14, 14′) that is mounted rotatably. The hydrodynamic slide bearing (10,10′) comprises a plurality of bearing segments (12, 12′) arranged next to one another in the rotation direction (22, 22′). The segment surfaces together form a running surface (16, 16′) for the shaft (14, 14′). At least one bearing segment (12, 12′) has a plurality of grooves (26, 26′) disposed in its segment surface, and the grooves (26, 26′) are orientated substantially transverse to the rotation direction (22, 22′). The rear groove edges (261) in the rotation direction (22, 22′) are orientated obliquely to their respective assigned radial plane (24, 24′) and are undercut in relation to their respective assigned radial plane (24, 24′). The front groove edges (262) in the rotation direction (22, 22′) are not undercut and are orientated obliquely to their respective assigned radial plane (24, 24′).

Claims

1. A hydrodynamic slide bearing (10, 10′) for supporting a shaft (14, 14′) that is rotatable in a rotation direction about an axis, the slide bearing (10, 10′) comprising: a plurality of bearing segments (12, 12′) arranged next to one another in the rotation direction (22, 22′), wherein the bearing segments (12, 12′) have segment surfaces that together form a running surface (16, 16′) for facing a surface of the shaft (14, 14′), the segment surface of at least one of the bearing segments (12, 12′) having a plurality of grooves (26, 26′) orientated substantially transverse to the rotation direction (22, 22′), wherein: each of the grooves (26, 26′) has a front groove edge (262) and a rear groove edge (261) disposed relative to one another so that a point moving along the respective segment surface in the rotation direction first passes an intersection of the segment surface with the front groove edge (262) and then passes an intersection of the segment surface with the rear groove edges (261), the rear groove edge (261) of each of the grooves (26, 26′) is orientated obliquely to a rear radial plane (24, 24′) that passes through both the axis and the rear groove edge (261), and each of the rear groove edges (261) is undercut in relation to same rear radial plane (24, 24′), and the front groove edges (262) of each of the grooves (26, 26′) is orientated obliquely to a front radial plane (24, 24′) that passes through both the axis and the front groove edge (262) and, each of the front groove edges (262) is not undercut in relation to the same front radial plane (24, 24′).

2. The hydrodynamic slide bearing (10,10′) of claim 1, wherein the undercut groove edges (261) are arranged at an angle of 5° to 20° relative to their respectively rear radial plane (24, 24′).

3. The hydrodynamic slide bearing (10,10′) of claim 1, wherein the grooves (26, 26′) are arranged in a groove arrangement region (28, 28′) that, in the rotation direction (22, 22′), begins at 60% to 65% of the segment length and ends at 90% to 95% of the segment length.

4. The hydrodynamic slide bearing (10,10′) of claim 3, wherein the grooves (26, 26′) are arranged in a groove arrangement region (28, 28′) that extends over a central 60% to 90% of the segment width.

5. The hydrodynamic slide bearing (10,10′) of claim 3, wherein the grooves (26, 26′) occupy 10% to 60% of an area of the groove arrangement region (28, 28′).

6. The hydrodynamic slide bearing (10,10′) of claim 1, wherein at least some of the grooves (26, 26′) are interrupted in their longitudinal extension direction.

7. The hydrodynamic slide bearing (10,10′) of claim 6, wherein two of the grooves (26, 26′) that are adjacent in the rotation direction have their interruptions arranged with respect to each other with an offset transverse to the rotation direction (22, 22′).

8. The hydrodynamic slide bearing (10,10′) of claim 1, wherein the running surface (16′) is planar and is oriented perpendicular to the axis and wherein the bearing segments (12′) are formed as circle ring sectors.

9. The hydrodynamic slide bearing (10,10′) of claim 1, wherein the running surface (16) is curved and oriented coaxial to the axis and the bearing segments (12) are formed as hollow cylinder sectors.

10. The hydrodynamic slide bearing (10,10′) of claim 1, further comprising oil supply regions (18, 18′) that extends transverse to the rotation direction (22, 22′), at least one of the oil supply regions being disposed between every two adjacent bearing segments (12, 12′), thereby separating them adjacent bearing segments (12, 12′).

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0023] FIG. 1 is a schematic cross-section depiction of a slide bearing according to the invention with a radial bearing design.

[0024] FIG. 2 is a schematic unrolled depiction of one of the bearing segments of the slide bearing from FIG. 1

[0025] FIG. 3 is a schematic cross-section depiction of a groove of a slide bearing according to the invention.

[0026] FIG. 4 is a schematic top view of a slide bearing according to the invention with an axial bearing design.

DETAILED DESCRIPTION

[0027] Identical reference numbers in the Figures refer to identical or analogous elements.

[0028] In a highly schematized depiction, FIG. 1 shows a cross-sectional view of a slide bearing 10 according to the invention with a radial bearing design. In the embodiment depicted, the slide bearing 10 is assembled from three bearing segments 12, the concave inner segment surfaces of which together form a running surface 16 arranged coaxially to the supported shaft 14. Oil supply regions 18 are arranged respectively between the individual bearing segments 12 Oil can be pulled through the oil supply regions 18 and into the bearing gap 20 formed between the shaft 14 and the running surface 16, for lubricating and cooling. The movement direction arrow 22 indicates the rotation direction of the shaft 14. The dash-dotted line represents a radial plane 24.

[0029] The rear region of the segment surfaces of the lower load-bearing bearing segments 12, as viewed along the rotation direction of the shaft 14 have a groove arrangement region 28 with grooves 26 arranged thereon. The upper bearing segments 12 bear less load of the shaft 14 and do not have a groove arrangement region in the shown exemplary embodiment, however, a groove arrangement region would be entirely possible with other embodiments. It has been shown, however, that in radial bearings, the grooves 26 according to the invention are especially and mostly adequately effective primarily in the segment surfaces of the supporting segment(s). Typically, these are the lower one to two bearing segments.

[0030] FIG. 4 shows a slide bearing 10′ with an analogous construction in an axial design. The dashed reference symbols used in FIG. 4 correspond to the non-dashed reference symbols from FIG. 1, wherein the bearing gap located within or parallel to the drawing plane is not apparent in FIG. 4. For axial bearings, usually all bearing segments 12′ carry an equal load, such that the grooves 26′ according to the invention are typically present in the segment surfaces of all segments. For clarity of the drawing, structures that are present in all segments are not marked for every segment with reference symbols, but rather representatively on a single illustrated segment.

[0031] In the shown slide bearings 10, 10′, each groove arrangement region 28, 28′ extends respectively over a region that begins after approx. 65% of the segment length in the rotation direction of the shaft 14 and ends after approx. 90% of the segment length. The groove arrangement region is therefore arranged at a distance of approx. 65% of the segment length from the preceding oil supply region 18, 18′ and of approx. 10% of the segment length from the following oil supply region 18, 18′.

[0032] As is evident for the axial bearing 10′ from FIG. 4 and for the radial bearing 10 from FIG. 2, the groove arrangement region does not extend over the entire segment width. Rather, it merely occupies centrally approx. 90% of the segment width.

[0033] As is evident from FIG. 2, in the shown axial bearing 10, the grooves 26 are formed as grooves that are interrupted in their longitudinal direction. The groove interruptions of two respective grooves arranged adjacently in the rotation direction are offset from one another transverse to the rotation direction.

[0034] FIG. 3 shows in detail, although in a highly schematic form, the fundamental form according to the invention of the grooves 26. This is characterized especially in that the rear groove edge 261, in the rotation direction, has an undercut with an undercut angle α opposite the assigned radial plane 24. The front groove edge 262 forms a comparatively slightly oblique surface that at the groove base 263, which is (insofar as is possible due to production technology) formed with an acute angle, abuts directly on the rear groove edge 261. In alternative embodiments, the groove base is not acute-angled but rather flat or formed with a radius, such that the front and rear groove edge 262, 261 do not directly meet one another there. Especially in such cases, a significantly steeper angle of the front groove edge 262 is conceivable. The effect of the undercut according to the invention is suggested by the swirl 30 in FIG. 3. The oil film flowing within the bearing gap 20 remains, so to speak, caught at the rear groove edge 261, such that its laminar structure is destroyed and it swirls. This results in an exchange of cooler oil fractions proximate to the shaft and warmer oil fractions proximate to the bearing. This results in a thermal equalization within the oil film, and this occurs in a bearing region in which the fresh oil fed in from the most recently passed oil supply region 18 is already significantly heated. Moreover, the chosen groove arrangement region 28 corresponds very precisely to the pressure drop region of the bearing.

[0035] Of course, the embodiments discussed in the description and shown in the figures are only illustrative exemplary embodiments of the present invention. This disclosure gives one skilled in the art a broad spectrum of possible variations. In particular, the number of the segments on which the grooves according to the invention are provided can vary.

REFERENCE SYMBOL LIST

[0036] 10 slide bearing (radial bearing) [0037] 10′ slide bearing (axial bearing) [0038] 12, 12′ bearing segment [0039] 14, 14′ shaft [0040] 16, 16′ running surface [0041] 18, 18′ oil supply region [0042] 20 rotation direction arrow [0043] 24, 24′ radial plane [0044] 26, 26′ groove [0045] 261 rear groove edge [0046] 262 front groove edge [0047] 263 groove base [0048] 28, 28′ groove arrangement region [0049] 30 swirl [0050] h groove depth [0051] d groove width (on the opening side)