Hydrodynamic plain bearing

Abstract

The invention relates to a hydrodynamic plain bearing (1) for supporting a rotor (4), said plain bearing comprising a bearing shell (2) having a bearing surface (3) for supporting the rotor, the bearing surface having at least one first sliding surface (10) and at least one second sliding surface (20), the first sliding surface (10) having at least one first surface portion (10a) which is eccentrically offset relative to a centre point (M0) of the bearing shell, and the second sliding surface (20) having at least one second surface portion (20a), wherein a) the second surface portion (20a) has, in at least one axial cross-section, a circular segment having a radius (R2), the centre point (M2) of which is not offset relative to the centre point (M0) of the bearing shell; and / or b) the second surface portion (20a) at least comprises: b1) at least one opening (8) inside a pocket (9) for supplying lubricant and / or coolant; b2) a wedge groove (23) which has at least one portion (24), the radial depth of which decreases, in particular continuously, in the peripheral direction up to a run-out edge (25) on the second sliding surface (20); and b3) a connection (21) for supplying the wedge groove (23) with lubricant and / or coolant from the pocket (9).

Description

[0001] Description

[0002] Hydrodynamic plain bearing

[0003] The present invention relates to a hydrodynamic plain bearing for supporting a rotor, a rotor arrangement, in one embodiment a gearbox, with at least one rotor which is supported by at least one plain bearing described here, and the use of a plain bearing described here for supporting a rotor.

[0004] The object of the present invention is to improve a bearing of a rotor or a hydrodynamic plain bearing provided for this purpose, in particular used.

[0005] This object is achieved by a hydrodynamic plain bearing having the features of claim 1. Claims 11 and 12 protect a rotor assembly, in one embodiment a gearbox, with one or more rotors, each of which is / are supported by one or more plain bearings described herein, or the use of a plain bearing described herein for supporting a rotor. The subclaims relate to advantageous developments.

[0006] According to one embodiment of the present invention, a hydrodynamic plain bearing which supports a rotor, preferably rotatably and / or at least radially, or is provided or configured or used for this purpose, has a one-part or preferably multi-part bearing shell, which in turn has, preferably on an inner circumference of the bearing shell, a bearing surface which supports the rotor or is provided or configured or used for this purpose, or a multi-part or preferably one-part (theoretical) bearing shell, which in turn has, preferably on an outer circumference of the bearing shell, a bearing surface which supports the rotor or is provided or configured or used for this purpose, in particular if the plain bearing has a plain bearing bolt or is designed as a plain bearing bolt.

[0007] In one embodiment, the rotor is a shaft, a journal, or the like; in a particularly advantageous embodiment, a gear shaft or the like. In one embodiment, the rotor is a gear, in particular a planet of a planetary gear. During operation, in particular during nominal operation, it rotates in a (main) direction of rotation around or relative to a (rotational) axis, preferably at high speed. Accordingly, in one embodiment, an axial or axial direction (of the plain bearing) mentioned here is parallel to the longitudinal and / or rotational axis of the rotor to be supported or supported, and a radial or radial direction is perpendicular to the axial direction and (main) rotational and / or circumferential direction.

[0008] In one embodiment, the plain bearing is designed as a plain bearing bush. In an alternative embodiment, the plain bearing is designed as a plain bearing pin. If the description presented here refers to a design with a plain bearing bush, this is to be understood without restriction of generality and is particularly transferable to a design with a plain bearing pin or vice versa. Accordingly, the term “bearing shell”, as used herein, should preferably be understood as a bearing shell with a radially inner bearing surface, in particular if the plain bearing is designed as a plain bearing bush or, if the plain bearing is designed in particular as a plain bearing pin, as a theoretical orimaginary bearing shell with a bearing surface lying radially outwards in relation to the plain bearing pin, in particular in such a way that the bearing shell in the case of a plain bearing designed as a plain bearing pin refers to an axial section which is intended or designed for a plain bearing or is used for this purpose. Accordingly, the direction of the grooves, openings, connections or the like is to be understood in such a way that, in designs in which the plain bearing is designed in particular as a plain bearing bush, these recess radially outwards into the bearing shell or bearing surface(s) or are designed accordingly, or, in designs in which the plain bearing is designed in particular as a plain bearing pin, these recess radially inwards into the bearing shell or bearing surface(s) or are designed accordingly.For the plain bearing designed as a plain bearing pin, in particular in one embodiment, the term “bearing shell”, as used herein, is to be understood as the, in particular unmachined, shaft into which the features described herein are incorporated or, in particular, are or are formed by machining.

[0009] According to one embodiment of the present invention, the bearing surface has at least two sliding surfaces, which are referred to herein, without limitation of generality, as the first and second sliding surfaces, respectively. In one embodiment, the first and second sliding surfaces each have an extension or an angle of 180°. In one embodiment, the first and second sliding surfaces do not overlap each other; in particular, they can be adjacent to each other on both sides or follow one another in the circumferential direction and together form (the) 360° of the bearing surface.

[0010] In one embodiment, the (rated load) vector of the (resulting and / or radial) bearing force that the rotating rotor exerts on the bearing during operation at maximum or rated speed and / or at maximum or rated load lies in the first sliding surface. At rest, the weight load vector or vector of the weight force that the stationary rotor exerts on the bearing can lie in the first or second sliding surface. In one embodiment, the first sliding surface is a loaded sliding surface or a so-called "load segment" and the second sliding surface is a non-loaded sliding surface or a so-called "non-load segment".

[0011] In a preferred embodiment, the bearing shell comprises a first shell part, which has the first sliding surface on its inner circumference, and at least one second shell part, which is connected to the first shell part and, in a further development, can be removed non-destructively and has the second sliding surface on its inner circumference. Particularly preferably, the first and second sliding surfaces adjoin one another at the dividing joints between these shell parts, especially when the plain bearing is designed as a plain bearing bush. This can simplify production in one embodiment.However, the present invention is not limited to this, in particular, in a likewise advantageous embodiment, the bearing shell can have a first shell part and at least one second shell part connected thereto, in a further development which can be detachably removed without destruction, wherein the first shell part has on its inner circumference a (surface) section of the first sliding surface and a (surface) section of the second sliding surface and / or the second shell part has on its inner circumference a (surface) section of the first sliding surface and a (surface) section of the second sliding surface.

[0012] According to one embodiment of the present invention, the first sliding surface has at least one surface section, which is referred to as the first surface section without restriction of generality and which is offset eccentrically to a center point, preferably the bearing axis, in particular formed by the outer, preferably cylindrical, surface of the bearing shell, preferably in such a way that, in the case of an imaginary (rotationally symmetrical) shaft (or its circular axial section) arranged centrally to the center point or the bearing axis, a gap convergent in the (main) direction of rotation is formed between the shaft and the first surface section. In particular, the first sliding surface can be identical to the first surface section, in particular if the plain bearing is designed as a plain bearing bush.In a further development, the first surface section has in one or more axial sections a circular segment with a radius, the center point of which is offset eccentrically to the center point, preferably the bearing axis, of the bearing shell, preferably in the manner explained above, the first surface section being preferably described in the axial section(s) by the circular segment.

[0013] As a result, in one embodiment, the lubrication and / or coolant supply can be improved during operation within the first surface section and / or the risk of (undesired) subsynchronous vibrations (in particular a half-frequency vortex / so-called “oil whirl”) in connection with higher speeds and lower bearing forces can be reduced, as is known in particular from so-called multi-wedge bearings, for example lemon bearings.

[0014] According to one embodiment of the present invention, the first sliding surface has at least one surface section, which is referred to as the first surface section without restriction of generality and which is offset eccentrically to a center point, preferably the bearing axis, preferably in such a way that, in the case of an imaginary (rotationally symmetrical) shaft (or its circular axial section) arranged centrally to the center point or the bearing axis, a gap convergent in the (main) direction of rotation is formed between the rotor and the first surface section, in particular the first sliding surface can be identical to the first surface section, in particular if the plain bearing is designed as a plain bearing bolt.In a further development, the first surface section has, in one or more axial sections, a circular segment with a radius whose center point is offset eccentrically from the center point, preferably the bearing axis, of the bearing shell, preferably in the manner explained above. Preferably, the first surface section is described by the circular segment in the axial section(s). As a result, in one embodiment, during operation within the first surface section, the lubrication and / or coolant supply can be improved and / or the risk of (undesired) subsynchronous vibrations (in particular a half-frequency vortex / so-called "oil whirl") associated with higher speeds and lower bearing forces can be reduced.According to one embodiment of the present invention, the second sliding surface has at least one surface section which, without restriction of generality, is referred to as the second surface section; in particular, the second sliding surface can be identical to the second surface section.

[0015] According to one aspect of the present invention, the second surface section has in one or more axial sections, preferably the axial section(s) mentioned above with reference to the first surface section, (in each case) a circular segment with a radius whose center point is centrally located to the center point, preferably the bearing axis, in particular formed by the outer, preferably cylindrical surface, of the bearing shell (executed) or is not offset from the center point, preferably the bearing axis, of the bearing shell, preferably the second surface section is described in the axial section(s) in each case by the circular segment, in particular when the plain bearing is designed as a plain bearing bush.

[0016] According to one aspect of the present invention, the second surface section has in one or more axial sections, preferably the axial section(s) mentioned above with reference to the first surface section, (in each case) a circular segment with a radius whose center point is centric to the center point of the bearing axis, in particular centric to the center point of the theoretical bearing shell, (executed) or is not offset from the center point of the bearing axis, in particular from the center point of the theoretical bearing shell, preferably the second surface section is described in the axial section(s) in each case by the circular segment, in particular when the plain bearing is designed as a plain bearing bolt.

[0017] As a result, in one embodiment, lubricant and / or coolant consumption and / or power loss can be reduced during operation within the second surface section. Thus, in one embodiment, a wedge bore with the first surface section is combined with a circular bore with the second surface section, in particular when the plain bearing is designed as a plain bearing bush, or, in one embodiment, a wedge segment with the first surface section is combined with a circular segment with the second surface section, in particular when the plain bearing is designed as a plain bearing pin. In one embodiment, a single-wedge bore bearing is thus formed, which in particular is not a multi-wedge bore bearing.

[0018] Alternatively or independently or particularly preferably in addition to this aspect of a combination of profiled loaded surface section and unprofiled unloaded surface section, according to one aspect of the present invention, the second surface section has at least:

[0019] - one or more openings within a pocket through which lubricant and / or coolant is supplied during operation or which is intended, arranged or used for this purpose;

[0020] - a keyway which has at least one section, in particular a surface section, the radial depth of which decreases continuously in the circumferential direction, preferably in the (main) direction of rotation, up to a run-out edge on the second sliding surface, preferably downstream in the (main) direction of rotation or direction of the shaft and / or in the outflow direction of the lubricant and / or coolant from the pocket and / or adjacent to the first sliding surface, wherein in one embodiment this section of the keyway in one or more axial sections, preferably the axial section(s) mentioned above with reference to the first or second surface section, (in each case) has a circular segment with a radius, the center point of which has an eccentricity to the center point, preferably the bearing axis, of the, in particular theoretical, bearing shell in such a way or is eccentrically offset therefrom in such a way that a radial depth (of the keyway orof the section) in the circumferential direction up to the outlet edge, in a preferred development continuously, is reduced, preferably described by this circle segment; and.

[0021] - a single- or multi-channel connection through which the keyway can be or is supplied with lubricant and / or coolant from, in particular from, the pocket or which is provided or designed or used for this purpose.

[0022] In this way, in one embodiment, at least a portion, preferably a majority, of the lubricant and / or coolant entering through the opening(s) can be guided from the pocket through the connection to the keyway and there experience a hydrodynamic back pressure within the wedge-like section of the keyway. As a result, in one embodiment, a lifting pressure can advantageously be brought about during operation with, in particular, low bearing loads, and thus the dynamic stability can be increased, advantageously in an efficient and effective manner, in particular intensified, in particular as a result of a smaller radial play of the unprofiled second surface section towards the rotor, and / or a displacement of the rotor towards the second surface section or unloaded segment can be reduced, preferably prevented, in particular at higher speeds.Compared to the well-known and widely used "pressure dam" groove, which usually has a constant axial width and constant depth and which has a sudden change in depth until shortly before the end of the groove or run-out in the direction of rotor rotation due to a tool run-out, a more advantageous pressure characteristic and thus a more advantageous (especially dynamic) effect on the shaft or the rotor can be achieved by designing the keyway, in particular the lifting pressure.

[0023] In one embodiment, the keyway or its section, the radial depth of which decreases in the circumferential direction up to the run-out edge, in a further development, the circular segment with the radius, the center of which has the eccentricity to the center or the bearing axis of the bearing shell such that a radial depth decreases in the circumferential direction up to the run-out edge, has a beginning which has a smaller distance or angular offset from the pocket in the circumferential direction than the run-out edge, and from which the radial depth decreases, preferably continuously, up to the run-out edge.

[0024] In one embodiment, the connection of or between the pocket and the keyway has one or more feed grooves, which (respectively) adjoin the pocket, wherein in a further development the one or more feed grooves each have, at least in sections, a width in the axial direction, in particular a maximum, average or minimum width, which is smaller than a width of the pocket in the axial direction, in particular a maximum, average or minimum width, and / or smaller than a width of the keyway in the axial direction, in particular a maximum, average or minimum width. In one embodiment, this allows the flow of lubricant and / or coolant from the pocket to the keyway to be improved. By limiting the width in the axial direction of the one or more feed grooves, in one embodiment, the hydrodynamic effect of the sliding surfaces located laterally of the feed groove(s) in the axial direction can advantageously be limited within the angular length orThe circumference of the feed groove(s) must be maintained.

[0025] Additionally or alternatively, in one embodiment, the connection of or between the pocket and the keyway has at least one distribution groove which, in a further development, adjoins the keyway and / or the feed groove and which has a width in the axial direction, in particular a maximum, average or minimum, which is greater than the width, in particular a maximum, average or minimum, of the feed groove. In one embodiment, this makes it possible to improve the flow of lubricant and / or coolant into or in the keyway, in particular a distribution, furthermore in particular an axial distribution. In one further development, the distribution groove has a width, in particular a maximum, average or minimum, in the axial direction, which is greater than or equal to the width, in particular a maximum, average or minimum, of the feed groove.

[0026] In one embodiment, the flow of lubricant and / or coolant into or in the keyway, in particular a distribution, in particular an axial distribution, can be further improved.

[0027] Accordingly, in a preferred embodiment, the feed groove(s) may be adjacent to the pocket and the keyway or connect them for the supply of lubricant and / or coolant, or particularly preferably the feed groove(s) may be adjacent to the pocket and the distribution groove and the distribution groove may be adjacent to the feed groove(s) and the keyway.

[0028] In one embodiment, the pocket and / or the supply groove(s) and / or the distribution groove and / or the keyway (each) are delimited on both axial sides of the plain bearing by the second surface section in order to guide at least a portion, preferably a majority, of the lubricant and / or coolant entering through the opening(s) to the keyway or to cause a hydrodynamic back pressure or lifting pressure there, particularly during partial load operation. In one embodiment, the plain bearing has a continuous transition between the circular segment with the radius of the first surface section and the circular segment with the radius of the second surface section. In this case, “continuous” is understood in particular to mean “continuous or continuously variable within the scope of or taking into account the manufacturing tolerance(s)”.

[0029] Such a continuous or stepless transition enables, in one embodiment, more advantageous, and in particular smoother, shaft displacement into the unloaded shell. Furthermore, in one embodiment, this can reduce the risk of instabilities and cavitation formation or damage to sliding surfaces. In a further development, in an offset plane which is spanned on the one hand by the axis of the bearing shell or the theoretical bearing shell and on the other hand by the center point of the circular segment with the radius of the first surface section and / or the center point of the circular segment with the radius of the second surface section, there is exactly one radial offset in the circumferential direction at the transition from the second surface section to the first surface section, wherein the continuous transition is formed in at least one axial section of the bearing shell on the opposite side as a result of the radii and the eccentricity of the first surface section.In one embodiment, the radial offset extends in the circumferential direction, in particular over several degrees, in particular at least 2° and / or at most 5°. In one embodiment, the radial offset is, at least substantially, continuous, in particular not abrupt or jumpy, and in one embodiment extends in the circumferential direction, in particular over several degrees, in particular at least 2° and / or at most 5°.

[0030] As a result, the advantageous continuous transition explained above can be realized in a particularly advantageous manner in terms of manufacturing technology, particularly in the case of a plain bearing designed as a plain bearing bush.

[0031] In one embodiment, the first surface section has one or more openings within a further pocket for supplying lubricant and / or coolant, wherein in a further development a beginning of this further pocket which is closer to the second surface section in the circumferential direction is pivoted by an angle which is at least 5° and / or at most 35° with respect to a, preferably the aforementioned, radial offset between the first surface section and the second surface section in the circumferential direction.

[0032] By means of such a pocket pivoted into the first, loaded sliding surface or its first surface section, preferably from a joint of the bearing shell, an undesirable hot lubricant and / or coolant carryover from the unloaded to the loaded sliding surface can be reduced in one embodiment and, in particular, as a result of this, by proportionally more cold lubricant and / or coolant, by supply from the pocket, with, in particular advantageously in one embodiment, a higher average viscosity, lead to lower maximum pressures and / or lower maximum temperatures in the loaded sliding surface.

[0033] In one embodiment, the inner bearing surface is radially and axially recessed by two or more radial recesses, preferably two recesses arranged on the edge or on both axial end faces of the bearing shell, wherein in a further development one or more of these recesses (each) extends in the circumferential direction at least over the entire circumference of the second sliding surface. Additionally or alternatively, in a further development one or more of these recesses (each) extends in the circumferential direction over a, preferably the aforementioned, radial offset between the first surface section and the second surface section (across) or, in a further development, one or more of these recesses (each) overlaps this in the circumferential direction.

[0034] In one embodiment, this allows hot lubricant and / or coolant to be advantageously removed or discharged from the bearing, particularly at the axial edges at the end of the loaded sliding surface; this reduces the average gap temperature and, in particular, the power loss.

[0035] In a further development, the recess(es) or one or more of these recesses extend in the first sliding surface in the circumferential direction from the radial offset over which it extends or overlaps, over an angle that is less than or equal to the angle by which the beginning of the further pocket is pivoted relative to this radial offset. In one embodiment, this allows the power loss to be further reduced, particularly in addition to the aforementioned advantages.

[0036] In a further development, the or one or more of these recesses in the first sliding surface extend in the circumferential direction from the radial offset over which it extends or which it overlaps, over an angle which is greater than the angle by which the beginning of the further pocket is pivoted relative to this radial offset.

[0037] In one embodiment, in particular in addition to the aforementioned advantages, the lubricant and / or coolant supply in the further pocket can be improved.

[0038] Particularly preferably, a difference between the angle between the radial offset and the end of the or one or more of the recesses in the first sliding surface and the angle by which the beginning of the further pocket is pivoted relative to this radial offset is at most 40°.

[0039] By limiting the recess area in one design, the maximum pressure and / or the bearing temperature in the loaded sliding surface can be reduced.

[0040] In one embodiment, the plain bearing is installed or used in such a way, in particular in a bearing arrangement, that an angle of between 50° and 70° is formed in the circumferential direction between the nominal load vector and the beginning of the pocket in the unloaded sliding surface.

[0041] In one embodiment, the depth of the connection is at least 2 times and / or at most 8 times greater than the smallest radial clearance within the plain bearing with a rotor located centrally in the bearing.

[0042] In one embodiment, the maximum depth of the keyway is preferably at least 0.3 times and / or at most 2.5 times the smallest radial clearance within the plain bearing with a rotor located centrally in the bearing. In one embodiment, the circumferential angle of the keyway is at least 15° and / or at most 50° and is in particular at least as large as the circumferential angle of the distribution groove.

[0043] The term "keyway," as used herein, should be understood in one embodiment as a wedge-shaped recess, in particular within a surface section (as described herein). The keyway can be or become axially delimited by a / the surface section in one embodiment. The term "keyway," as used herein, should preferably not be understood as a wedge gap and / or a wedge bore, in particular a wedge gap of a wedge bore, further in particular of a (multi-)wedge bore bearing, and these terms should preferably not be understood as a synonym for "keyway."

[0044] In one embodiment, the circumferential angle of the feed groove is at least 40° and / or at most 100°.

[0045] In one embodiment, the axial width of the, in particular all, feed grooves in the unloaded sliding surface, in particular in total, is at least 15% and / or at most 45% of the axial width of the loaded sliding surface.

[0046] A plain bearing according to the invention can, in one embodiment, reduce lubricant and / or coolant consumption and / or power loss and / or maximum temperature. It is particularly advantageous to use one or more plain bearings described here for supporting at least one rotor, preferably one or more plain bearings described here for supporting a first rotor and one or more plain bearings described here for supporting at least one further rotor of a preferably high-speed transmission. A lubricant and / or coolant mentioned here can, in particular, comprise oil, preferably be oil. Nevertheless, the present invention is not limited to such applications or oil.

[0047] Further advantages and features emerge from the subclaims and the exemplary embodiments. The following shows, partly schematically:

[0048] Fig. 1 : a side view of a plain bearing of a rotor arrangement according to a

[0049] Embodiment of the present invention; and Fig. 2: a developed view of an inner circumference of a bearing shell of the plain bearing or a developed view of the outer circumference of the plain bearing pin shown in Fig. 3;

[0050] Fig. 3: a side view of a plain bearing of a rotor assembly according to an embodiment of the present invention.

[0051] Fig. 1 shows a side view of a plain bearing 1, in particular a plain bearing 1 designed as a plain bearing bush, for supporting a rotor 4 of a rotor arrangement with a rotor (main) direction of rotation 5 according to an embodiment of the present invention, Fig. 2 a developed view of an inner circumference of a bearing shell 2 of the plain bearing.

[0052] The bearing shell here comprises two bearing shell parts (top, bottom in Fig. 1) that adjoin one another at a joint (horizontal, dot-dash line in Fig. 1; L1, L2 in Fig. 2) and are connected to one another in a manner not shown. The upper bearing shell in Fig. 1 has a first sliding surface 10 of 180° on its inner circumference, while the lower bearing shell in Fig. 1 has a second sliding surface 20 of 180° on its inner circumference. These two sliding surfaces 10, 20 together form an inner bearing surface 3 of the plain bearing 1 or the bearing shell 2. A (nominal load) vector of the (resulting and / or radial) bearing force F, which the rotating rotor exerts on the bearing during operation at maximum or nominal speed and / or at maximum or nominal load, lies in the first sliding surface, so that this or the upper bearing shell part in Fig. 1 forms a or the loaded sliding surface or a orforms the loaded segment, and the second sliding surface, or the lower bearing shell part in Fig. 1, forms the unloaded sliding surface or the unloaded segment, or the non-loaded segment. This is particularly advantageous from a manufacturing perspective, but the invention is not limited to an identity of the sliding surfaces and the bearing shell parts (adjacent to one another in joints).

[0053] The first, loaded sliding surface 10 has a first surface section 10a or a wedge bore, which in the side view of Fig. 1 is described by a circle segment with a radius R1, the center M1 of which is eccentric to the center MO, which is formed by the radius RO of the circle of the outer cylindrical surface of the bearing shell (eccentricity e1).

[0054] The second, unloaded sliding surface 20 has a second surface section 20a or a circular bore, which in the side view is described by a circle segment with a radius R2, the center M2 of which is central to the center MO, which is formed by the radius RO of the circle of the outer cylindrical surface of the bearing shell.

[0055] As can be seen in particular in the side view of Fig. 1 combined with the development of Fig. 2, the second surface section 20a of the unloaded sliding surface 20 has the following elements:

[0056] - (exemplarily two) openings 8 within a lubrication pocket 9 for supplying lubricant and / or coolant;

[0057] - a feed groove 21 extending in the circumferential direction (horizontally in Fig. 2), which adjoins or extends to the lubrication pocket 9;

[0058] - a distribution groove 22 extending in the circumferential direction, which adjoins or extends to the feed groove 21;

[0059] - a keyway 23 extending in the circumferential direction, which adjoins or extends to the distribution groove 22, this keyway 23 having a (surface) section 24 which, in the side view of Fig. 1, is described by a circular segment with a radius Rk, the center Mk of which has an eccentricity ek to the center MO of the bearing shell such that the radial depth of the keyway 23 decreases continuously in the circumferential direction up to its outlet edge 25 on the unloaded sliding surface 20.

[0060] The grooves 21, 22, which connect the pocket 9 to the keyway 23, as well as the keyway 23 itself, are each delimited on the two axial sides of the plain bearing by the second surface section 20a, so that a large part of the lubricant or coolant entering through the openings 8 is guided from the pocket 9 via the grooves 21, 22 to the keyway 23.

[0061] The feed groove 21 in the unloaded sliding surface 20 is smaller in its axial length than the keyway 23. The distribution groove 22 in the unloaded sliding surface 20 is larger in its axial length than the feed groove 21.

[0062] L1 denotes a boundary line between an end of the second, unloaded sliding surface 20 and a beginning of the first, loaded sliding surface, and L2 denotes a corresponding boundary line: between an end of the first, loaded sliding surface and a beginning of the second, unloaded sliding surface.

[0063] In the offset plane 30, which is spanned by the centers M1, M2 and the axis of rotation of the bearing shell, there is exactly one radial offset 31 in the circumferential direction at the transition L1 of the second surface section 20a of the second, unloaded sliding surface 20 to the first surface section 10a of the first, loaded sliding surface 10, wherein in the above-mentioned side view of the bearing shell on the opposite side, a continuous transition 32, L2 without radial offset is formed due to the radii R1, R2 and the eccentricity e1 of the first surface section 10a.

[0064] A further lubrication pocket 7 with an opening 6 in the first surface section 10a is pivoted out of the offset plane 30, wherein the angle in the circumferential direction starting from the offset plane 30 with the radial offset 31 to the beginning of the lubrication pocket 7 is between 5° and 35°.

[0065] The inner bearing surface 3 is radially and axially recessed by two radial recesses 35 beginning at the front edges of the second sliding surface 20, with both recesses extending in the circumferential direction of the shaft over the entire circumference of the second, unloaded sliding surface 20 (section 35a) and, in their angular extension 35b in the circumferential direction beyond the radial offset 31, each assuming an angle a. In the exemplary embodiment, this angle a is smaller than the angle between the offset plane and the beginning of the lubrication pocket 7 in the circumferential direction. In a modification, the angle a can also be as large as or larger than the angle.

[0066] Fig. 3 shows a side view of a plain bearing 1, in particular a plain bearing 1 designed as a plain bearing pin, for supporting a rotor 4 of a rotor arrangement with a rotor (main) direction of rotation 5 according to an embodiment of the present invention, wherein, for simplification, (only) that part of a shaft designed as a plain bearing pin which has the plain bearing is shown as a side view; Fig. 2 shows a developed view of an outer circumference of the plain bearing 1, in particular of the plain bearing 1 designed as a plain bearing pin.

[0067] The plain bearing pin here has two (theoretical) bearing shell parts (top, bottom in Fig. 3) that adjoin each other at a joint (horizontal, dot-dash line in Fig. 3; L1, L2 in Fig. 2). The upper theoretical bearing shell in Fig. 3 has a first sliding surface 10 of 180° on its outer circumference, while the lower theoretical bearing shell in Fig. 3 has a second sliding surface 20 of 180° on its outer circumference. These two sliding surfaces 10, 20 together form an outer bearing surface 3 of the plain bearing (pin) 1. A (nominal load) vector of the (resulting and / or radial) bearing force F, which the rotating rotor exerts on the bearing or the plain bearing pin during operation at maximum or nominal speed and / or at maximum or nominal load, lies in the first sliding surface, so that this or the upper theoretical bearing shell part in Fig. 3 is a or the loaded sliding surface or a orforms the loaded segment, and the second sliding surface, or the theoretical bearing shell part shown in Fig. 3 below, forms the unloaded sliding surface or the unloaded segment, or the non-loaded segment. This is particularly advantageous from a manufacturing perspective, but the invention is not limited to the identical sliding surfaces and (theoretical) bearing shell parts.

[0068] The first, loaded sliding surface 10 has a first surface section 10a, which in the side view of Fig. 1 is described by a circle segment with a radius R1, the center M1 of which is eccentric to the center MO, which is formed by the radius R0 of the circle of the outer cylindrical surface of the theoretical bearing shell (eccentricity e1).

[0069] The second, unloaded sliding surface 20 has a second surface section 20a, which in the side view is described by a circular segment with a radius R2, whose center M2 is central to the center MO, which is defined by the radius R0 of the circle of the outer cylindrical surface of the theoretical bearing shell. As can be seen particularly in the side view of Fig. 3 combined with the developed view of Fig. 2, the second surface section 20a of the unloaded sliding surface 20 has the following elements:

[0070] - (exemplarily two) openings 8 within a lubrication pocket 9 for supplying lubricant and / or coolant, wherein the plain bearing pin in one embodiment has an axial, in particular coaxial, bore which is fluidically connected to the (exemplarily two) openings 8, in particular is designed to supply the (exemplarily two) openings 8;

[0071] - a feed groove 21 extending in the circumferential direction (horizontally in Fig. 2), which adjoins or extends to the lubrication pocket 9;

[0072] - a distribution groove 22 extending in the circumferential direction, which adjoins or extends to the feed groove 21;

[0073] - a keyway 23 extending in the circumferential direction, which adjoins or extends to the distribution groove 22, this keyway 23 having a (surface) section 24 which, in the side view of Fig. 1, is described by a circular segment with a radius Rk, the center Mk of which has an eccentricity ek to the center MO of the theoretical bearing shell such that the radial depth of the keyway 23 decreases continuously in the circumferential direction up to its outlet edge 25 on the unloaded sliding surface 20.

[0074] The grooves 21, 22, which connect the pocket 9 to the keyway 23, as well as the keyway 23 itself, are each delimited on the two axial sides of the plain bearing by the second surface section 20a, so that a large part of the lubricant or coolant entering through the openings 8 is guided from the pocket 9 via the grooves 21, 22 to the keyway 23.

[0075] The feed groove 21 in the unloaded sliding surface 20 is smaller in its axial length than the keyway 23.

[0076] The distribution groove 22 in the unloaded sliding surface 20 is larger in its axial length than the feed groove 21.

[0077] L1 is a boundary line between one end of the second, unloaded

[0078] Sliding surface 20 and a beginning of the first, loaded sliding surface, with L2 a corresponding boundary line: between an end of the first, loaded sliding surface and a beginning of the second, unloaded sliding surface.

[0079] In the offset plane 30, which is spanned by the centers M1, M2 and the axis of rotation of the bearing shell, there is exactly one radial offset 31 in the circumferential direction at the transition L1 of the second surface section 20a of the second, unloaded sliding surface 20 to the first surface section 10a of the first, loaded sliding surface 10, wherein in the above-mentioned side view of the bearing shell on the opposite side, a continuous transition 32, L2 without radial offset is formed due to the radii R1, R2 and the eccentricity e1 of the first surface section 10a.

[0080] A further lubrication pocket 7 with an opening 6 in the first surface section 10a is pivoted out of the offset plane 30, wherein the angle in the circumferential direction starting from the offset plane 30 with the radial offset 31 to the beginning of the lubrication pocket 7 is between 5° and 35°.

[0081] The inner bearing surface 3 is radially and axially recessed by two radial recesses 35 beginning at the front edges of the second sliding surface 20, with both recesses extending in the circumferential direction of the shaft over the entire circumference of the second, unloaded sliding surface 20 (section 35a) and, in their angular extension 35b in the circumferential direction beyond the radial offset 31, each occupying an angle a. In the exemplary embodiment, this angle a is smaller than the angle between the offset plane and the beginning of the lubrication pocket 7 in the circumferential direction. In a modification, the angle a can also be as large as or larger than the angle.

[0082] In the present disclosure, "has an X" generally does not imply an exhaustive list, but is a shortened form of "has at least one X" and also includes "has two or more Xs" and "has Y in addition to X." Although exemplary embodiments have been explained in the foregoing description, it should be noted that numerous modifications are possible. Furthermore, it should be noted that the exemplary embodiments are merely examples and are not intended to limit the scope, applications, or construction in any way.Rather, the foregoing description provides the person skilled in the art with a guide for the implementation of at least one exemplary embodiment, whereby various changes, in particular with regard to the function and arrangement of the described components, can be made without departing from the scope of protection as it results from the claims and combinations of features equivalent to these.

[0083] List of reference symbols

[0084] 1 Hydrodynamic plain bearing

[0085] 2 bearing shell

[0086] 3 Storage area (inside or outside)

[0087] 4 Rotor

[0088] 5 Direction of rotation of the rotor

[0089] 6 Opening

[0090] 7 bag

[0091] 8 Opening

[0092] 9 bag

[0093] 10 first, loaded sliding surface

[0094] 10a first (loaded) area section

[0095] 20 second, unloaded sliding surface

[0096] 20a second (unloaded) area section

[0097] 21 Feed groove

[0098] 22 Distribution groove

[0099] 23 Keyway

[0100] 24 area section

[0101] 25 run-out edge

[0102] 30 offset level

[0103] 31 radial offset

[0104] 32 continuous transition

[0105] 35 radial recess

[0106] 35a Section of the radial recess in the second, unloaded sliding surface

[0107] 35b Section of the radial recess in the first, loaded sliding surface

[0108] F Nominal load vector

[0109] L1 boundary line: end of second, unloaded sliding surface / beginning of first, loaded sliding surface

[0110] L2 boundary line: end of first, loaded sliding surface / beginning of second, unloaded sliding surface

[0111] R0 Radius of the circle of the outer cylindrical surface of the bearing shell or the theoretical bearing shell R1 Radius of the circular segment of the first surface section

[0112] R2 Radius of the circular segment of the second surface section

[0113] Rk radius of the circular segment of the keyway

[0114] MO Center of the circle of the outer cylindrical surface of the, in particular theoretical, bearing shell

[0115] M1 Center of the circle segment of the first area section

[0116] M2 Center of the circular segment of the second area section

[0117] Mk Center of the circular segment of the keyway e1 Eccentricity of the circular segment of the first surface section ek Eccentricity of the keyway a Angle between offset plane and recess end Angle between offset plane and beginning of the next pocket

Claims

Patent claims 1. A hydrodynamic plain bearing (1) for supporting a rotor (4), comprising a bearing shell (2) with a bearing surface (3) for supporting the rotor, wherein the bearing surface has at least a first sliding surface (10) and at least one second sliding surface (20), wherein the first sliding surface (10) has at least a first surface section (10a) which is offset eccentrically to a center point (MO) of the bearing shell, and the second sliding surface (20) has at least a second surface section (20a), wherein a) the second surface section (20a) has, in at least one axial section, a circular segment with a radius (R2), the center point (M2) of which is not offset from the center point (MO) of the bearing shell; and / or b) the second surface section (20a) has at least: b1) at least one opening (8) within a pocket (9) for supplying lubricant and / or coolant;b2) a keyway (23) having at least one section (24) whose radial depth decreases, in particular continuously, in the circumferential direction up to a run-out edge (25) on the second sliding surface (20); and b3) a connection (21) for supplying the keyway (23) with lubricant and / or coolant from the pocket (9).

2. Plain bearing (1) according to the preceding claim, characterized in that the connection - at least one feed groove (21) which adjoins the pocket (8) and has, at least in sections, a width in the axial direction which is smaller than a width of the pocket (8) and / or keyway (23) in the axial direction; and / or - at least one distribution groove (22), in particular adjoining the keyway (23) and / or feed groove (21), which has a width in the axial direction that is greater than the width of the feed groove (21); 3. Plain bearing (1) according to one of the preceding claims, characterized in that - the first surface section (10a) has, in at least one axial section, a circular segment with a radius (R1), the center (M1) of which is offset eccentrically from the center (MO) of the bearing shell; and / or - the section (24) of the keyway (23), the radial depth of which decreases up to the run-out edge (25), has in at least one axial section a circular segment with a radius (Rk), the center point (Mk) of which has an eccentricity (ek) with respect to the center point (MO) of the shell such that the radial depth decreases in the circumferential direction up to the run-out edge, in particular continuously.

4. Plain bearing (1) according to the preceding claim, characterized by a continuous transition (32) between the circular segment with the radius (R1) of the first surface section (10a) and the circular segment with the radius (R2) of the second surface section (20a).

5. Plain bearing (1) according to the two preceding claims, characterized in that in an offset plane (30) which is spanned by the axis of the bearing shell and the center point (M1) of the circular segment with the radius (R1) of the first surface section (10a) and / or the center point (M2) of the circular segment with the radius (R2) of the second surface section (20a), there is exactly one radial offset (31) in the circumferential direction at the transition of the second surface section (20a) to the first surface section (10a).

6. Plain bearing (1) according to one of the preceding claims, characterized in that the first surface section (10a) has at least one opening (6) within a further pocket (7) for supplying lubricant and / or coolant.

7. Plain bearing (1) according to the preceding claim, characterized in that a beginning of the further pocket (7) closer to the second surface section (20a) in the circumferential direction is offset relative to a radial offset (31) between the first surface section (10a) and the second surface section (20a) in Circumferential direction is pivoted by an angle ( ) of at least 5° and / or at most 35°.

8. Plain bearing (1) according to one of the preceding claims, characterized in that the inner bearing surface (3) is radially and axially recessed by at least two radial recesses (35), wherein at least one of the recesses extends in the circumferential direction at least over the complete circumference of the second sliding surface (20) and / or over at least one radial offset (31) between the first surface section (10a) and the second surface section (20a).

9. Plain bearing (1) according to claim 7 and 8, characterized in that the at least one recess extends in the first sliding surface (10) in the circumferential direction from the radial offset (31) between the first surface section (10a) and the second surface section (20a) over an angle (a) which is less than or equal to the angle ( ) by which the beginning of the further pocket (7) is pivoted relative to the radial offset (31).

10. Plain bearing (1) according to claim 7 and 8, characterized in that the recess extends in the first sliding surface (10) in the circumferential direction from the radial offset (31) between the first surface section (10a) and the second surface section (20a) over an angle (a) which is greater than the angle ( ) by which the beginning of the further pocket (7) is pivoted relative to the radial offset (31).

11. Rotor arrangement, in particular a gearbox, with at least one plain bearing (1) according to one of the preceding claims and a rotor mounted thereby.

12. Use of a plain bearing (1) according to one of the preceding claims for supporting a rotor (4).

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