TAPERED ROLLER BEARING

Abstract

A tapered roller bearing having a diameter of less than 1.5 m includes an inner ring having at least one inner raceway, an outer ring having at least one outer raceway and at least one set of tapered rollers between the inner ring and the outer ring that are configured to roll on the at least one inner raceway and on the at least one outer raceway about a tapered-roller rotational axis while the tapered roller bearing is configured to rotate about a bearing rotational axis. An angle formed by the bearing rotational axis and the tapered-roller rotational axis is greater than 450 and is preferably between 500 and 55.

Claims

1. A tapered roller bearing having a diameter of less than 1.5 m, comprising: an inner ring having at least one inner raceway, an outer ring having at least one outer raceway, the inner ring and the outer ring being rotatable with respect to each other, and at least one set of tapered rollers disposed between the inner ring and the outer ring configured to roll on the at least one inner raceway and the at least one outer raceway about a tapered-roller rotational axis, the tapered roller bearing being configured to rotate about a bearing rotational axis, wherein an angle formed by the bearing rotational axis and the tapered-roller rotational axis is greater than 45.

2. The tapered roller bearing according to claim 1, wherein the angle is between 45 and 65.

3. The tapered roller bearing according to claim 1, wherein the outer ring includes a guide flange for guiding the tapered rollers, the guide flange being formed one-piece with the outer ring.

4. The tapered roller bearing according to claim 1, wherein the outer ring is one-part and the inner ring is two-part.

5. The tapered roller bearing according to claim 1, wherein the outer ring is fixed and the inner ring is rotatable.

6. The tapered roller bearing according to claim 1, wherein the outer ring includes an outer flange, and wherein an axial thickness of the outer flange is less than an axial thickness of the outer ring.

7. The tapered roller bearing according to claim 1, wherein the at least one inner raceway and/or the at least one outer raceway have a straight profile.

8. The tapered roller bearing according to claim 1, wherein the tapered rollers have a crowned profile.

9. The tapered roller bearing according to claim 1, wherein an edge clearance between an edge of an axial end side of each tapered roller and the inner raceway and/or the outer raceway is less than 20 m.

10. The tapered roller bearing according to claim 1, wherein the at least one set of tapered rollers comprises a first set of tapered rollers and a second set of tapered rollers axially spaced from the first set of tapered rollers.

11. The tapered roller bearing according to claim 10, wherein a ratio of a diameter of the inner ring and a minimum axial spacing of geometric center points of a tapered roller of the first set of tapered rollers and a tapered roller of the second set of tapered rollers is smaller than 15.

12. The tapered roller bearing according to claim 1, wherein a variance of a diameter measured at an axial center of each of the tapered rollers is less than 1 m.

13. A high-precision machine-tool table with a tapered roller bearing according to claim 1.

14. The tapered roller bearing according to claim 1, wherein the angle is between 50 and 55.

15. The tapered roller bearing according to claim 1, wherein an edge clearance between an edge of an axial end side of each tapered roller and the inner raceway and/or the outer raceway is between 1 m and 10 m.

16. The tapered roller bearing according to claim 10, wherein a ratio of an inner diameter of the inner ring and a minimum axial spacing of geometric center points of a tapered roller of the first set of tapered rollers and a tapered roller of the second set of tapered rollers is between 8 and 12.

17. The tapered roller bearing according to claim 1, wherein the at least one inner raceway comprises a first inner raceway and a second inner raceway, wherein the at least one outer raceway comprises a first outer raceway and a second outer raceway, wherein the at least one set of tapered rollers comprises a first set of tapered rollers between the first outer raceway and the first inner raceway and a second set of tapered rollers between the second outer raceway and the second inner raceway, wherein the angle is between 50 and 55, wherein the outer ring includes a first guide flange configured to guide the first set of tapered rollers and a second guide flange configured to guide the second set of tapered rollers, wherein the outer ring includes an outer flange projecting away from the inner ring, wherein an axial thickness of the outer flange is less than an axial thickness of the outer ring, wherein the tapered rollers of the first and second sets of tapered rollers are crowned, and wherein an edge clearance between an edge of an axial end side of each tapered roller and the inner raceway and/or the outer raceway is between 1 m and 10 m.

18. The tapered roller bearing according to claim 17, wherein a ratio of an inner diameter of the inner ring and an axial spacing of a geometric center point of a tapered roller of the first set of tapered rollers and a geometric center point of a tapered roller of the second set of tapered rollers is between 8 and 12.

Description

[0020] In the following the invention is described in more detail using the exemplary embodiments depicted in the drawings. Here the exemplary embodiments and the combinations shown in the exemplary embodiments are purely exemplary and are not intended to define the scope of the invention. This scope is defined solely by the pending claims.

[0021] FIG. 1 shows a sectional view through a tapered roller bearing according to one embodiment, and

[0022] FIG. 2 shows a schematic view of a section of FIG. 1.

[0023] In the following, identical or functionally equivalent elements are designated by the same reference numbers.

[0024] FIG. 1 shows a tapered roller bearing 1 that includes an inner ring 2 and an outer ring 4, wherein the inner ring 2 is comprised of a first part 2-1 and a second part 2-2 that are connected to each other by an attachment means 6. The tapered roller bearing 1 has a diameter of less than 1.5 m.

[0025] In the tapered roller bearing 1 shown in FIG. 1, the outer ring 4 is fixed, whereas the inner ring 2 is designed to rotate about a rotational axis X. Alternatively, the outer ring 4 can also be configured rotating, and the inner ring can be configured fixed. The tapered roller bearing 1 can in particular be a high-precision tapered roller bearing.

[0026] Between the inner ring 2 and the outer ring 4, a set of tapered rollers 8 is disposed wherein the set of tapered rollers 8 roll on an inner raceway 10 associated with the inner ring 2 and on an outer raceway 12 associated with the outer ring 4. The tapered roller bearing 1 is preferably a double row tapered roller bearing, i.e., two sets of tapered rollers 8-1, 8-2 are provided that each roll on associated inner and outer raceways 10-1, 10-2, 12-1, 12-2.

[0027] In order to simplify the installation of the tapered rollers 8, the tapered roller bearing 1 can include a cage 20 that is designed to hold and to guide the tapered rollers 8. The cage 20 can in particular be manufactured from a plastic material. Alternatively, the cage 20 can also be manufactured from a metal.

[0028] In order to increase the tilt rigidity of the tapered roller bearing 1, in the tapered roller bearing 1 the raceways, i.e., the inner and outer raceways 10-2, 10-2, 12-1, 12-2, are configured such that an angle that is formed between the bearing rotational axis X and a tapered-roller rotational axis 14 of a respective tapered roller 12 is greater than 45. The tapered-roller rotational axis 14 is understood to mean the rotational axis about which the tapered roller 8 rotates. The angle that is formed between the bearing rotational axis X and a tapered-roller rotational axis 14 of a respective tapered roller 8 is preferably between 45 and 65, most preferably between 50 and 55.

[0029] Furthermore, a guide flange 16 is provided on the fixed outer ring 4. The guide flange 16 is formed one-piece with the outer ring 4 and configured to guide the tapered rollers 8. The outer raceways 12-1, 12-2 of the outer ring 4 are preferably formed by grinding, wherein the guide flanges 16 are simultaneously formed on the outer ring 4.

[0030] Furthermore, the outer ring 4 is provided with a flange 18 that extends toward the outer side of the tapered roller bearing 1. Here a thickness t.sub.F of the flange is narrower in the axial direction than a thickness t.sub.A of the outer ring 4. Furthermore, a ratio d/A of a diameter d of the inner ring 2 and a spacing A of the geometric center points of the tapered rollers 8 of the row is preferably smaller than 15, d/A<15, in particular falls between 8d/A12.

[0031] FIG. 2 shows a schematic depiction of a section of FIG. 1 in which the profiles of the inner raceway 10, of the outer raceway 12, and of the tapered roller 8 are shown. In the tapered roller bearing 1 of FIG. 1, the inner raceways 10-1, 10-2 and the outer raceways 12-1, 12-2 have a straight profile. A straight profile is understood in particular to mean that the profile is flat and does not have a crowned shape. In contrast thereto, the tapered rollers 8 have a slightly crowned profile, i.e., the profile has a slight, in particular a convex, curvature. This is indicated schematically in FIG. 2. The dashed lines 22 show a theoretical straight profile course, while the continuous lines show the slightly crowned course of the tapered roller profile.

[0032] In particular, an edge clearance r between an end surface 24 of the tapered roller 8 and the inner raceway 10 and/or the outer raceway 12 can be less than 20 m, preferably between 1 m and 10 m.

[0033] In summary, a tapered roller bearing 1 is provided in which the angle formed between the bearing rotational axis X and the tapered-roller rotational axis 14 is greater than 45. The tilt rigidity of the tapered roller bearing can thus be increased, whereby the high accuracy of the tapered roller bearing 1 is improved even at high rotational speeds.

REFERENCE NUMBER LIST

[0034] 1 Tapered roller bearing [0035] 2 Inner ring [0036] 4 Outer ring [0037] 6 Attachment means [0038] 8 Tapered roller [0039] Inner raceway [0040] 12 Outer raceway [0041] 14 Tapered-roller rotational axis [0042] 16 Guide flange [0043] 18 Flange [0044] 20 Cage [0045] 22 Line [0046] 24 Edge of the tapered roller [0047] A Spacing of the tapered roller rows [0048] X Bearing rotational axis [0049] t.sub.A Thickness of the outer ring [0050] t.sub.F Thickness of the flange [0051] d Diameter of the inner ring [0052] r Edge clearance