Roller bearing

Abstract

This invention relates to a roller bearing, particularly a double-row self-aligning roller bearing, comprising an inner ring and an outer ring, and a plurality of rolling bodies rolling in two rows on corresponding raceways on the inner and outer rings, wherein the inner ring and / or the outer ring is radially split to form at least two annular portions, wherein the raceways (17a, 17b; 18a, 18b) have wear patterns in the abutment region between the two annular portions (7a, 7b; 8a, 8b; 10a, 10b) that locally deepen the raceways (17a, 17b; 18a, 18b). Grinding recesses (19, 20), wherein each of the grinding recesses (19) on the outer ring (2) extends along the circumferential direction of the raceway (17) of the outer ring (2) for a length that corresponds at most to the circumferential distance (X) between the contact point (B1) of the first rolling body (4) and the raceway (17) and the contact point (B2) of the rolling body (4) and the raceway, the rolling body being separated from the first rolling body (4) by one rolling body, and the length being greater than half the diameter (D) of the rolling body (4) at its maximum diameter point.

Description

Technical Field

[0001] The present invention relates to roller bearings, particularly double-row self-aligning roller bearings, which include an inner ring and an outer ring, and a plurality of rolling bodies rolling in two rows on corresponding raceways on the inner and outer rings, wherein the outer ring is radially split to form at least two annular portions. Background Technology

[0002] For example, such double-row self-aligning roller bearings are known from DE 10 2011 086 925 A1. The self-aligning roller bearings described therein are characterized in that the outer ring and / or inner ring comprises two annular portions or annular halves, which are circumferentially adjacent to each other; that is, the corresponding rings are radially split, wherein, in each case, a radial split plane is provided. Such split rings are mainly used in large bearings because this makes bearing installation easier. Due to the multi-part nature of the inner ring and / or outer ring, their parts can be assembled individually. Such bearings are used, for example, in complex transmission systems and offer the advantage that, in the event of bearing failure, the bearing can be replaced without partially or completely disassembling the transmission system.

[0003] The corresponding rings are typically split because they fracture at defined points or in defined planes, thus eliminating material removal during separation—unlike material removal if the ring were sawn open. Defined fracture lines are formed during fracture, meaning the ring material fractures along grain boundaries, with the fracture lines advancing in the desired plane. During assembly, the corresponding ring portions are then reassembled. In the case of a split inner ring, the split inner ring is secured to the shaft, for example, by means of clamping rings extending around the sides, while the split outer ring is inserted into the corresponding housing component.

[0004] Therefore, the present invention is based on the objective of specifying a relatively improved self-aligning roller bearing.

[0005] If, for example, a roller bearing or self-aligning roller bearing split in this manner is used in a wind turbine, the rolling body, rolling on the raceway of the annular portion and over the transition between the annular portions, subjects the contact point between the annular portions to high loads. It has been found that due to ring fracture, the fracture line of the ring extends transversely to the raceway, and small, minute peaks or uneven sections may exist at the edges of the annular portion on the raceway side due to the microstructure of the ring material. If, during operation, the rolling body rolls over this slightly damaged raceway area, this can lead to damage to the raceway over time, and the rolling body itself may also be damaged. To prevent this phenomenon, a precise contact area is known from DE10 2017 110 742 A1, in which the raceway sections of the two annular portions of the contact area are connected to the grinding recess, that is, the raceway is slightly locally deepened in the contact area, in which the cross-section of the raceway has a continuous direction, thereby creating a groove-shaped or hollow deepening in the contact area, the depth and width of which are only a few tenths of a millimeter to a few millimeters.

[0006] However, the connecting devices between the corresponding annular portions forming the outer ring of a roller bearing are subjected to significant stress. For example, in the operation of split roller bearings, it has been shown that the connecting devices between the annular portions of the outer ring can become loose or even detach, leading to bearing damage.

[0007] Therefore, the present invention aims to provide a split roller bearing, particularly a self-aligning roller bearing, which has an improved service life relative to the connecting device between the annular portions. Summary of the Invention

[0008] If at least each grinding recess on the outer ring has an arcuate path extending transversely to the abutment region, wherein the maximum radial depth T of the grinding recess is located exactly in the abutment region, and each grinding recess extends circumferentially along the raceway of the outer ring for a length at most equal to the circumferential distance X between the contact point of the first rolling body and the raceway and the contact point of the rolling body and the raceway, wherein the rolling body is spaced one rolling body apart from the first rolling body, and the length is greater than half the diameter of the rolling body at its maximum diameter point, and on the two sides of the abutment region between the two formed annular portions are formed tracks for the rolling body to pass through or enter, the tracks gradually decreasing the pressure of the rolling body in the raceway in their function as exit tracks until reaching the direct abutment region, and gradually increasing the pressure on the rolling element after the direct abutment region has rolled into the raceway in their function as entry tracks. According to the applicant's findings, the progressive transition specifically ensures that the connecting device is almost or not at all loaded when rolling through the abutment region circumferentially, but such a force alone causes elastic deformation of the annular portion.

[0009] It is advantageous if the depth T of the grinding recess is between 0.05 and 0.0001* of the diameter D of the rolling body at its maximum diameter point, because such a depth T does not require any measures to compensate for the weakening of the outer ring.

[0010] Assembly and disassembly are simplified if the inner and / or outer rings are radially split into more than two annular portions, wherein a grinding recess is provided in each abutment region. Here, it is preferable that the outer ring is split into two planes extending in a mutually orthogonal manner. The ring then comprises four circumferential annular portions, for example at 90° angles, which are complementary to each other in circumferential respect. In this case, four abutment points are provided on the split ring, each having a corresponding grinding recess.

[0011] An advantageous improvement of the invention involves an outer ring axially splitting into two partial rings to form annular portions arranged axially adjacent to each other. According to this configuration, if the outer ring is not radially split, it will be split into two separate partial rings axially adjacent to each other. Due to the axial split, there are then two annular portions, each of which forms a one-piece partial ring. However, if the outer ring splits into circumferentially complementary annular portions in one or more radial planes, and if the outer ring is also split along an axial plane, there are multiple corresponding annular portions that are circumferentially complementary to each other to form partial rings, wherein, on the other hand, two multi-part partial rings then complement each other to form the entire outer ring. If the outer ring is radially split into two annular portions, for example, along a plane, and also axially split, there are a total of four annular portions, each of which forms a partial ring. If the outer ring is radially split into two mutually orthogonal planes, and if axial splitting is also provided, there are a total of eight annular portions, wherein four annular portions are complementary to each other to form partial rings. This axial split also simplifies bearing installation, especially when the bearing is asymmetrical.

[0012] It is conceivable that, in the assembled position, the partial rings are supported against each other, wherein at least one radial bore is provided for supplying lubricant to the interior of the bearing in the region of the axial separation point. Thus, the partial rings are in direct contact with each other here. For bearing lubrication, it is advantageous to provide one or more radial bores that penetrate the assembled outer ring in the region of the separation plane or separation point. This can be used to supply lubricant to the interior of the roller bearing to achieve permanent lubrication.

[0013] As an alternative, it is conceivable that the two partial rings are axially spaced to form an annular gap. This axial spacing can be made, for example, by lightly grinding the axial end faces, meaning less material is removed. If the partial rings are now mounted and pushed onto the rolling bodies of each row, it is impossible to push the partial rings to come into full contact with each other without causing an unacceptably high bearing preload due to the grinding or material removal. This means that a circumferential clearance exists, through which lubricant can be supplied. On the other hand, a preload or bearing clearance can be set for one or both rows of rolling bodies, depending on how the respective partial rings are axially positioned relative to the rolling bodies of the respective row. This design ensures that, from an axial perspective, the two partial rings will not contact each other even when the bearing clearance is zero, i.e., there is no operating clearance or a low preload is set.

[0014] In addition to the outer ring, the inner ring can also be divided into one or more planes. This also has corresponding grinding recesses in the corresponding abutment areas.

[0015] If the inner ring is also radially split, it is recommended to use a suitable clamping ring to hold it on the shaft. For example, these clamping rings, which also include two annular halves, are positioned at one end around the split inner ring and screwed together so that the inner ring is securely clamped on the shaft.

[0016] Each rolling body is preferably housed in or guided within a rolling body cage. The rolling body cage secures or guides the corresponding rolling body, in this case a self-aligning roller, and is preferably made of metal, such as a sheet metal component, although embodiments made of plastic are not excluded. It is advantageous if each rolling body cage is radially split to form at least two cage segments, which in turn facilitates assembly.

[0017] Self-aligning roller bearings can be asymmetrical bearings, meaning that the contact angles of the first and second rows of rolling elements are different. Preferably, identical rolling elements are used in both rows, unlike prior art, particularly according to DE 10 2011 086 925 A1, where different rolling elements are arranged in the two rows. However, self-aligning roller bearings can also be symmetrical bearings, in which identical contact angles exist. Attached Figure Description

[0018] In the attached diagram:

[0019] Figure 1 A partial perspective view of a double-row self-aligning roller bearing according to the present invention is shown.

[0020] Figure 2a It shows Figure 1The cross-sectional view of the self-aligning roller bearing section taken along line II-II.

[0021] Figure 2b An embodiment of the grinding recess according to the present invention is shown.

[0022] Figure 3 It shows along Figure 1 The cross-sectional view taken from line III-III in the diagram, and

[0023] Figure 4 With Figure 3 The corresponding cross-sectional view illustrates a second exemplary embodiment of the self-aligning roller bearing according to the present invention. Detailed Implementation

[0024] The invention will now be explained in more detail with reference to the accompanying drawings.

[0025] Figure 1 An asymmetric double-row self-aligning roller bearing 1 according to the present invention is shown. This asymmetric double-row self-aligning roller bearing includes an outer ring 2, an inner ring 3, and a plurality of rolling bodies 4 that roll between the outer ring 2 and the inner ring 3, for example, see Figure 2. These rolling bodies are in the form of barrel-shaped rollers, as can be... Figure 3 As observed in [the document]. The two scroll bodies 4 are identical, see, for example, [the document]. Figure 3 and Figure 4 Such bearings can be used, for example, in wind turbines. In this application, the bearings typically have several 100 mm widths.

[0026] In the example shown, the outer ring comprises two partial rings 5a and 5b after it has split along the axial plane 6, as shown in... Figure 3 and Figure 4 As specifically shown in the text.

[0027] In addition, each partial ring 5a, 5b includes two annular portions 7a, 7b or 8a, 8b, see [link to relevant documentation] Figure 1 The two annular portions are circumferentially complementary to each other to form corresponding partial rings 5a and 5b. See also... Figure 1 The outer ring 2 is thus split along the radial plane 9. This means that the outer ring 2 is split as a whole along the axial plane 6 and the radial plane 9 into a total of four annular portions 7a, 7b and 8a, 8b, which are complementary to each other to form two circumferential partial rings 5a, 5b.

[0028] In the example shown, the inner ring 3 is also split along the radial plane 11 into two annular portions 10a and 10b. These annular portions 10a and 10b are also circumferentially complementary to each other to form the inner ring 3. However, as Figure 3As shown, the inner ring does not split axially; the inner ring splits only along the radial plane 11.

[0029] To secure the inner ring 3 to a shaft (not shown) or similar object, two clamping rings 12 and 13 are provided. Each clamping ring includes two clamping annular portions 12a and 12b or 13a and 13b, which are securely connected to each other via corresponding threaded connectors 14, thereby firmly clamping the split inner ring 3, located at its axial end portion, onto the shaft. For this purpose, the inner ring 3 may have corresponding annular groove-shaped engagement geometry 15 and 16 at the respective ends, in which the clamping rings 12 and 13 are engaged in a form-fitting manner.

[0030] As described, the ring can fracture along the corresponding plane 6, and particularly plane 9, to split. Due to the material, typically steel, this means that after fracture along the grain boundaries, there are undefined fracture zones visible from the surface, causing local peaks or inhomogeneities when the annular portions are circumferentially assembled, particularly in the edge regions of annular portions 7a, 7b, 8a, 8b or 10a, 10b, where corresponding raceways 17, 18 are positioned on the outer ring 2 or inner ring 3. These defects are now eliminated because grinding recesses 19, 20 are formed in the abutment region of the two annular portions, see [reference needed]. Figure 2a This grinding recess forms a deepened portion 21, 22 with a depth T ranging from a few tenths of a millimeter to several millimeters, such as... Figure 2a As shown, the deepening portion 22 is by no means proportional in principle. The grinding recesses 19, 20 or the deepening portions 21, 22 extend over the entire length of the axial abutment portion. Figure 2b The design of a deepening portion 21 or grinding recess 19 on the outer ring 2 or between the annular portions 8a, 8b forming the outer ring 2 according to the present invention is shown. The grinding recess 19 shown here is introduced into the raceway 17 of the outer ring 2 as an arc-shaped, radially outwardly pointing deepening portion 21, wherein the maximum radial depth T of the deepening portion 21 is given at the position where the two annular portions 8a, 8b abut against each other. According to... Figure 2b In an exemplary embodiment, the depth T is approximately 0.025 times the diameter D of the rolling body 4. Figure 2bIn the exemplary embodiment shown, the recess 21 has a certain width—that is, a circumferential range—which corresponds to the diameter D of the rolling body 4 rolling between the bearing rings 2 and 3. This relatively large width of the recess 21 between the two annular portions 8a and 8b of the outer ring 2 serves a dual purpose: the corresponding abutment area is made unloaded due to the corresponding grinding recess 19 (20) and its extension in the circumferential direction of the bearing 1. In this way, although structural inhomogeneity is inevitable in the abutment area due to fracture, permanent operation can be ensured because the corresponding raceways in the abutment area will not be loaded and thus damaged. Furthermore, the large extension of the deepening portion 21 (22) in the circumferential direction of the bearing 1 also ensures... Figure 2b The fitting screw 29, which connects the two rings 8a, 8b forming the outer ring 2, will not be loaded by the circumferential rolling element 4 during the operation of the bearing 1, even if the bearing ring 2 formed by the annular portions 8a, 8b deviates to some extent from the shape of an ideal ring. Instead, the large circumferential range of the arcuate deepening portion 21 (22), together with the tangential transition area of ​​the raceway and the grinding recess 19 (20), forms the engagement or disengagement engagement area for the rolling body 4, which has passed through the direct contact point between the two annular portions 8a, 8b. In order for the corresponding deepening portions 21, 22 to produce the effect of releasing the engagement and disengagement engagement areas of the screw 29, the width of the deepening portions 21, 22 in the circumferential direction should be equal to or greater than half the diameter D of the rolling body 4 used. The beneficial effects of the deepened portions 21 and 22 are no longer significant when their range in the circumferential direction is greater than the circumferential distance X between the contact point B1 between the first rolling body 4 and the raceway 17 and the contact point B2 between the rolling body 4 and the raceway, wherein the rolling body is separated from the first rolling body 4 by one rolling body.

[0031] Figure 3 It shows along according to Figure 1 A cross-sectional view taken from line III-III. As can be observed, the rolling body 4 is designed as a barrel-shaped roller that rolls on corresponding raceways 17a, 18a or 17b, 18b of the inner ring 3 and partial rings 5a, 5b. Each rolling body is housed in and guided within cages 23, 24, which may also be radially divided into at least two cage halves. According to... Figure 3 In an exemplary embodiment, the two partial rings 5a, 5b are axially abutted against each other, that is, the two partial rings are in contact with each other in the region of the axial plane 6 that separates them. One or more radial holes 25 are provided to allow for lubrication supply.

[0032] Because of the Figure 3The fact that some rings 5a and 5b are axially resting in the implementation means that it is impossible to adjust the bearing clearance in the rolling body of the corresponding column, and therefore there is no clearance compensation.

[0033] In comparison, Figure 4 An embodiment of the double-row self-aligning roller bearing 1 is shown, which is in this respect similar to that according to... Figures 1 to 3 The corresponding implementation method, particularly regarding the formation of corresponding annular segments and corresponding grinding recesses 19, 20 at the abutment area. However, according to Figure 4 In this embodiment, the rings 5a and 5b are not positioned such that they rest axially against each other; instead, a circumferential annular gap 26 is formed, through which lubricant can be supplied. This annular gap 26 can be formed by grinding the rings on the end faces 27a and 27b of the rings 5a and 5b, which means that a small amount of material is removed.

[0034] On the other hand, such as Figure 4 As shown, since the partial rings do not contact each other, the clearance or bearing clearance in the rolling bodies of the corresponding columns can be adjusted, with the small clearance 28 shown as the clearance in the region of the right-hand bearing column. This clearance or bearing clearance can be set by proper axial positioning of the corresponding partial rings 5a, 5b, but can also be fully compensated if needed, meaning that there is then no clearance or bearing clearance, and a low preload can be set if necessary. In any case, the two partial rings 5a, 5b will not contact each other axially, even when a low preload is set, as this would ultimately limit the setting options.

[0035] Finally, as Figure 3 and Figure 4 As shown, the self-aligning roller bearing 1 is an asymmetric self-aligning roller bearing because the contact angles of the two rows of rolling bodies are slightly different. The contact angle of the row of rolling bodies shown on the right is slightly larger than that of the row of rolling bodies shown on the left. The contact angles are shown as examples with α and β. However, the rolling bodies 4 of both rows of rolling bodies are identical.

[0036] Although in the described example, the outer ring 2 and the inner ring 3 are circumferentially split into two annular portions 7a, 7b or 8a, 8b relative to the outer ring 2 and circumferentially split into two annular portions 10a, 10b relative to the inner ring 3, it is certainly conceivable to radially split one or two rings into two preferably orthogonal planes such that each ring or portion of the ring would then comprise four complementary annular segments.

[0037] List of reference numerals

[0038] 1 Self-aligning roller bearings

[0039] 2 Outer Ring

[0040] 3 Inner Ring

[0041] 4. Scrolling Body

[0042] 5a Partial Ring

[0043] 5b Partial Ring

[0044] 6. Axial plane

[0045] 7a Ring-shaped part

[0046] 7b Ring-shaped part

[0047] 8a Circular section

[0048] 8b Ring-shaped part

[0049] 9. Radial plane

[0050] 10a Ring-shaped part

[0051] 10b Ring-shaped part

[0052] 11 Radial plane

[0053] 12a Clamping ring portion

[0054] 12b Clamping ring portion

[0055] 13a Clamping ring portion

[0056] 13b Clamping ring portion

[0057] 14 Threaded fasteners

[0058] 15 Joining Geometry

[0059] 16 Joining Geometry

[0060] 17 Roller Track

[0061] 17a raceway

[0062] 17b raceway

[0063] 18 raceways

[0064] 18a raceway

[0065] 18b raceway

[0066] 19 Grinding the recess

[0067] 20 Grinding recess

[0068] 21. Deepened section

[0069] 22 Deepening section

[0070] 23. Cage

[0071] 24. Cage

[0072] 25 radial holes

[0073] 26. Annular gap

[0074] 27a Front

[0075] 27b Front

[0076] 28 gaps

[0077] 29. Fitting screws

[0078] 30 shafts, unthreaded

Claims

1. A roller bearing comprising an inner ring and an outer ring, and a plurality of rolling bodies rolling in two rows on corresponding raceways (17a, 17b; 18a, 18b) on the inner ring (3) and the outer ring (2), wherein, The inner ring (3) and / or the outer ring (2) are radially split to form at least two annular portions, wherein the raceway has grinding recesses (19, 20) in the abutment region between the two annular portions (7a, 7b; 8a, 8b; 10a, 10b) that locally deepen the raceway (17a, 17b; 18a, 18b). Its features are, At least each grinding recess (19) on the outer ring (2) has an arcuate path extending transversely to the abutment region, wherein the maximum radial depth (T) of the grinding recess is located exactly in the abutment region, and each grinding recess (19) extends along the circumferential direction of the raceway (17) of the outer ring (2) for a length at most equal to the circumferential distance (X) between the contact point (B1) of the first rolling body and the raceway (17) and the contact point (B2) of the second rolling body and the raceway, the second rolling body being an interval of one rolling body relative to the first rolling body. The body, and the length of the rolling body (4) is greater than half the diameter (D) at the maximum diameter point of the rolling body, at least one fitting screw (29) is provided in the abutment area of ​​every two annular portions (7a, 7b; 8a, 8b; 10a, 10b), the fitting screw connecting the two annular portions (7a, 7b; 8a, 8b; 10a, 10b), wherein the abutment area between the corresponding annular portions (7a, 7b; 8a, 8b; 10a, 10b) intersects with each unthreaded shaft (30) of the corresponding fitting screw (29).

2. The roller bearing according to claim 1, Its features are, The depth (T) of the grinding recess is between 0.05 and 0.0001 times the diameter (D) at the maximum diameter point of the rolling body.

3. The roller bearing according to claim 1 or 2, Its features are, The inner ring (3) and / or the outer ring (2) are radially divided into more than two annular portions (8a, 8b; 10a, 10b), wherein a grinding recess (19, 20) is provided in each abutment region.

4. The roller bearing according to claim 1 or 2, characterized in that, The inner ring (3) and / or the outer ring (2) are each split into two planes (9) that extend in a mutually orthogonal manner.

5. The roller bearing according to claim 1 or 2, characterized in that, The outer ring (2) is axially split into two partial rings (5a, 5b) to form annular portions (7a, 7b; 8a, 8b) that are axially adjacent to each other.

6. The roller bearing according to claim 5, characterized in that, The partial rings (5a, 5b) are supported against each other, wherein at least one radial hole (25) is provided for supplying lubricant to the interior of the bearing in the region of the axial separation point.

7. The roller bearing according to claim 5, characterized in that, The two partial rings (5a, 5b) are axially spaced apart from each other to form a gap (26).

8. The roller bearing according to claim 1 or 2, characterized in that, The contact angle (α) of the first column of rolling bodies is different from the contact angle (β) of the second column of rolling bodies, wherein the rolling bodies of the two columns of rolling bodies are the same.

9. The roller bearing according to claim 1 or 2, characterized in that, Each column of rolling bodies (4) is housed in a corresponding rolling body retainer (23, 24).

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