Roller bearing and profile modification method for roller bearing

Abstract

A roller bearing and a profile modification method for the roller bearing. The roller bearing comprises: an outer ring; an inner ring, wherein the inner ring is disposed in the outer ring; and a roller, wherein the roller is disposed between the inner ring and the outer ring, the inner ring and the outer ring provide a raceway for the roller, a clearance is reserved between the roller and the raceway, the radial center surface of the roller and the raceway have an intersection, and the clearance is asymmetric relative to the intersection in the axial direction of the roller. The roller bearing provided in embodiments of the present invention is beneficial to mitigating the problem of uneven stress distribution of the roller, improving the bearing capacity of the roller bearing, and prolonging the service life of the roller bearing.

Description

Roller bearings and roller bearing modification methods Technical Field

[0001] This invention relates to the field of bearing design and manufacturing technology, and in particular to a roller bearing and a method for modifying roller bearings. Background Technology

[0002] To improve the boundary stress concentration, or "edge effect," problem at both ends of the rolling elements in straight-line roller bearings under load, modified roller bearings have gradually replaced traditional straight-line bearings in many important fields. By modifying the roller bearing, edge stress concentration caused by the contact between the rolling elements and the inner and outer rings can be avoided or reduced.

[0003] Currently, after modification, the common roller bearings have the contact point between the roller and the raceway at the axial center of the raceway, and the clearance between the roller and the raceway is symmetrical about the center with respect to the contact point. However, such roller bearings will experience stress concentration at one end under eccentric loading, resulting in limited bearing load capacity and service life.

[0004] Summary of the Invention

[0005] The technical problem solved by the present invention is to provide a roller bearing and a method for modifying the roller bearing, which can improve the bearing load capacity problem caused by stress concentration at one end of the roller bearing and help extend the service life of the bearing.

[0006] To solve the above-mentioned technical problems, embodiments of the present invention provide a roller bearing, comprising: an outer ring; an inner ring disposed within the outer ring; and a roller disposed between the inner ring and the outer ring, wherein the inner ring and the outer ring provide raceways for the roller, a gap exists between the roller and the raceways, the radial center plane of the roller intersects with the raceways at a point, and the gap is asymmetrical with respect to the intersection point in the axial direction of the roller.

[0007] Optionally, the roller includes a first portion and a second portion disposed relative to the radial center plane of the roller, the diameter of the second portion being larger than the diameter of the first portion, the first portion having a first gap with the raceway, and the second portion having a second gap with the raceway, the second gap being larger than the first gap.

[0008] Optionally, the ratio of the second gap to the first gap, which is equidistant from the intersection point, is less than or equal to 5.

[0009] Optionally, the gap is formed by modifying the roller, or by modifying the raceway, or by modifying both the roller and the raceway simultaneously.

[0010] Optionally, the rollers may be modified in sections or continuously; the raceways may be modified in sections or continuously.

[0011] Optionally, the raceway includes an inner raceway located on the outer circumferential surface of the inner ring and an outer raceway located on the inner circumferential surface of the outer ring; the modification of the raceway includes the modification of the inner raceway and / or the modification of the outer raceway.

[0012] Optionally, the intersection point coincides with the center point of the raceway, or the intersection point is offset from the center point of the raceway.

[0013] Optionally, the offset between the intersection point and the center point of the raceway is less than 30% of the raceway length.

[0014] Accordingly, embodiments of the present invention also provide a method for modifying a roller bearing, comprising: providing a roller bearing, the roller bearing including an outer ring, an inner ring, and a roller located between the outer ring and the inner ring, the inner ring and the outer ring providing a raceway for the roller, and the radial center plane of the roller intersecting the raceway; modifying the roller of the roller bearing, or modifying the raceway, or modifying both the roller and the raceway simultaneously, so that the gap between the roller and the raceway is asymmetrical with respect to the intersection point in the axial direction of the roller.

[0015] Optionally, the rollers may be modified in sections or continuously; the raceways may be modified in sections or continuously.

[0016] Optionally, the roller includes a first portion and a second portion disposed relative to the radial center plane of the roller, wherein the diameter of the second portion is larger than the diameter of the first portion.

[0017] Optionally, when modifying the roller, the modification includes modifying the first part and the second part, wherein the modification amount of the second part is greater than the modification amount of the first part.

[0018] Optionally, the raceway includes an inner raceway located on the outer circumferential surface of the inner ring and an outer raceway located on the inner circumferential surface of the outer ring.

[0019] Optionally, when modifying the raceway, the modification includes modifying the inner raceway and / or modifying the outer raceway, wherein the modification amount of the raceway located on the second part side is greater than the modification amount of the raceway located on the first part side.

[0020] Optionally, when both the roller and the raceway are modified, the sum of the modification amount of the second part and the modification amount of the raceway located on one side of the second part is greater than the sum of the modification amount of the first part and the modification amount of the raceway located on one side of the first part.

[0021] Optionally, the first portion has a first gap with the raceway, and the second portion has a second gap with the raceway, the second gap being larger than the first gap.

[0022] Optionally, the ratio of the second gap to the first gap, which is equidistant from the intersection point, is less than or equal to 5.

[0023] Compared with the prior art, the technical solution of the embodiments of the present invention has the following beneficial effects:

[0024] The roller bearing provided by this technical solution has rollers positioned between an inner ring and an outer ring. The inner and outer rings provide raceways for the rollers. The clearance between the rollers and the raceways is asymmetrical relative to the intersection of the rollers and the raceways in the axial direction of the rollers. Different clearance sizes can adjust the load distribution of the rollers, improve the problem of uneven stress distribution, increase the load-bearing capacity of the roller bearing, reduce roller wear, and thus help to improve the service life of the rollers.

[0025] The roller bearing modification method provided in this technical solution involves modifying the roller, the raceway, or both simultaneously, so that the gap between the roller and the raceway is asymmetrical relative to the intersection point in the axial direction of the roller. Different gap sizes can adjust the load distribution of the roller, improve the problem of uneven stress distribution, increase the load-bearing capacity of the roller bearing, reduce roller wear, and thus help to extend the service life of the roller. Attached Figure Description

[0026] Figure 1 is an axial cross-sectional view of a roller bearing in one embodiment;

[0027] Figure 2 is a load diagram of the roller bearing shown in Figure 1 after omitting the outer ring;

[0028] Figure 3 is an axial cross-sectional view of the roller in one embodiment of the present invention;

[0029] Figure 4 is an axial cross-sectional view of a roller bearing according to an embodiment of the present invention;

[0030] Figure 5 is a schematic diagram of the intersection point deviating from the center point of the raceway in another embodiment of the present invention;

[0031] Figure 6 is a schematic diagram of continuous roller modification in one embodiment of the present invention;

[0032] Figure 7 is a schematic diagram of roller segment modification in one embodiment of the present invention;

[0033] Figure 8 is a schematic diagram of asymmetric modification of the inner raceway in another embodiment of the present invention. Detailed Implementation

[0034] As described in the background section, currently, symmetrically modified roller bearings suffer from uneven stress distribution under extreme loads or off-center load conditions. The following analysis is based on specific embodiments.

[0035] Referring to Figure 1, the roller bearing includes: an inner ring 10, which includes an inner ring raceway 11; an outer ring 20, which includes an outer ring raceway 21 opposite to the inner ring raceway 11; and a roller 30 disposed between the inner ring raceway 11 and the outer ring raceway 21. The contact point between the center plane y of the roller 30 and the inner ring raceway 11 and the outer ring raceway 21 is o, which is located at the axial center of the raceway. The gap between the roller 30 and the inner ring raceway 11 and the outer ring raceway 21 is symmetrical about the contact point o.

[0036] The inventors discovered that in symmetrically modified roller bearings, with contact point o as the center, the clearance on both sides of contact point o is equal in size and equidistant from contact point o. Referring to Figure 2, the thick arrow in the figure represents the load and the thin arrow represents the stress. Under eccentric loading conditions, the roller bearing will experience uneven stress on the rollers. The roller on the side with the greater load has a larger contact area with the raceway and greater contact stress. This makes the roller on the side with the greater load more prone to wear during operation and has a shorter service life.

[0037] To address the aforementioned problems, embodiments of the present invention provide a roller bearing and a method for modifying the roller bearing. The roller bearing includes an inner ring, an outer ring, and rollers located between the inner and outer rings. The inner and outer rings provide raceways for the rollers. A gap exists between the rollers and the raceways, and the radial center plane of the rollers intersects with the raceways. The gaps are asymmetrical relative to the intersection points in the axial direction of the rollers, meaning that the gaps equidistant from the intersection points are not equal in size. Under eccentric loading conditions, the roller bearing has a larger gap at the end with a larger load. The rollers at the end with a smaller gap can balance the stress of the rollers at the end with a larger gap, resulting in a more uniform stress distribution. This reduces wear on the rollers at the end with a larger load, thereby extending the service life of the rollers.

[0038] To make the above-mentioned objectives, features and beneficial effects of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0039] Figure 3 is an axial cross-sectional view of the roller in one embodiment of the present invention; Figure 4 is an axial cross-sectional view of the roller bearing in one embodiment of the present invention; Figure 5 is a schematic diagram of the intersection point deviating from the center point of the raceway in another embodiment of the present invention.

[0040] Referring to Figures 3 and 4, the roller bearing includes an outer ring 100; an inner ring 200 disposed within the outer ring 100; and rollers 300 disposed between the inner ring 200 and the outer ring 100. The inner ring 200 and the outer ring 100 provide raceways for the rollers 300. A gap exists between the rollers 300 and the raceways. The radial center plane Y of the rollers 300 intersects with the raceways. The gap is asymmetrical with respect to the intersection point in the axial direction of the rollers 300.

[0041] In this invention, the radial center plane Y of the roller 300 refers to the center plane that is parallel to the radial direction of the roller 300 and parallel to the center plane of the two end faces of the roller 300, and the vertical distance between the two end faces of the roller 300 and the radial center plane Y is equal.

[0042] In this embodiment, the raceway includes an outer raceway 101 located on the inner circumferential surface of the outer ring 100 and an inner raceway 201 located on the outer circumferential surface of the inner ring 200. The roller 300 is disposed between the inner raceway 201 and the outer raceway 301, and the roller 300 has contact points with both the inner raceway 201 and the outer raceway 101.

[0043] In this embodiment of the invention, the contact point is the first intersection point O1 between the radial center plane Y of the roller 300 and the outer raceway 101, and the second intersection point O2 between the radial center plane Y and the inner raceway 201. The line connecting the first intersection point O1 and the second intersection point O2 is on the same plane as the radial center plane Y.

[0044] In this embodiment, the gaps relative to the intersection points are asymmetrical in the axial direction of the rollers 300. Specifically, taking the gap between the inner raceway 101 and the rollers 300 as an example, with the first intersection point O1 as the center, the gaps between the points on the generatrix of the rollers 300 on both sides of the first intersection point O1 that are equidistant from the first intersection point O1 and the inner raceway 201 are not equal.

[0045] In this embodiment, the gap between the roller and the raceway is designed asymmetrically. Under eccentric loading conditions, the roller at the end with the larger load has a larger gap with the raceway. The increased gap can reduce the contact stress of the roller at the end with the larger load, thereby achieving a uniform stress distribution on the roller, improving the load-bearing capacity of the roller bearing, reducing the wear of the roller at the end with the larger load, and helping to extend the service life of the roller.

[0046] In this embodiment, the asymmetry of the gap is continuous; in other embodiments, the asymmetry of the gap can be segmented, that is, it adopts a partially symmetrical and partially asymmetrical form.

[0047] In this embodiment, the roller 300 includes a first portion 301 and a second portion 302 disposed relative to the radial center plane Y. The first portion 301 has a first gap (unmarked) with the raceway, and the second portion 302 has a second gap (unmarked) with the raceway. The second gap is larger than the first gap.

[0048] In this embodiment, the second gap being greater than the first gap means that the width of the second gap between the second part and the raceway is greater than the width of the first gap between the first part and the raceway.

[0049] In this embodiment, the roller 300 is a tapered roller, and the diameter of the second part 302 is larger than the diameter of the first part 301. The roller of the second part 302 bears a larger load during operation. Expanding the second gap can change the contact area between the second part 302 and the raceway, reduce the contact stress of the second part 302, thereby improving the problem of uneven stress distribution of the roller 300, reducing the wear of the second part 302, and extending the service life of the roller 300.

[0050] In this embodiment, the ratio of the second gap to the first gap, which is equidistant from the intersection point, is less than or equal to 5. Specifically, the ratio of the width of the second gap to the width of the first gap is less than or equal to 5. Similarly, taking the gap between the inner ring raceway 101 and the roller 300 as an example, with the intersection point O1 as the center, there are a second gap and a first gap between the point on the generatrix of the second part 302 and the generatrix of the first part 301, which are equidistant from O1, and the inner ring raceway 201. The ratio of the second gap to the first gap is less than or equal to 5. The reason for setting this ratio range is to avoid excessively large differences between the second and first gaps causing stress concentration in the first part 301, which is more conducive to balancing the stress distribution of the first part 301 and the second part 302, and thus improving the overall load-bearing capacity of the roller bearing.

[0051] In other embodiments, the roller may also be a cylindrical roller or a self-aligning roller, etc.

[0052] The intersection of the radial center plane Y of the roller 300 and the raceway can coincide with the center point of the raceway, or the intersection of the radial center plane Y of the roller 300 and the raceway can deviate from the center point of the raceway.

[0053] Specifically, the intersection point can coincide with the center point of the raceway, which means that the second intersection point O2 of the radial center plane Y and the inner raceway 201 coincides with the center point of the inner raceway 201, and the first intersection point O1 of the radial center plane Y and the outer raceway 101 coincides with the center point of the outer raceway 101.

[0054] In another embodiment, referring to FIG5, taking the inner raceway as an example, inner raceway 201' shows an unmodified or symmetrically modified inner raceway, and inner raceway 201 shows the inner raceway of this embodiment. The intersection point deviating from the center point of the raceway refers to the second intersection point O2 of the radial center plane Y and the inner raceway 201 deviating from the center point P of the inner raceway 201. After the intersection point deviates from the center point of the raceway, the gaps on both sides of the intersection point are asymmetrical, and the gap on the side with the same direction of deviation is smaller than the gap on the side with the opposite direction of deviation.

[0055] When the first gap between the first part 301 of the roller 300 and the raceway is less than the second gap between the second part 302 and the raceway, the offset direction is from the second part 302 to the first part 301.

[0056] The deviation of the intersection point of the radial center plane of the roller 300 and the raceway from the center point of the raceway is less than 30% of the raceway length. Setting the offset to less than 30% of the raceway length can avoid stress concentration at the end of the roller 300 near the intersection point due to excessive offset, and avoid uneven stress distribution caused by offset.

[0057] The raceway length described in this invention is the length of the raceway along the axial direction of the roller.

[0058] Accordingly, embodiments of the present invention also provide a method for modifying the above-mentioned roller bearing, which will be described in detail below.

[0059] Figure 6 is a schematic diagram of continuous roller modification; Figure 7 is a schematic diagram of segmented roller modification; Figure 8 is a schematic diagram of inner ring raceway modification.

[0060] To create an asymmetrical gap, the gap can be formed by modifying the roller 300 or the raceway; or, the gap can be formed by modifying both the roller 300 and the raceway simultaneously.

[0061] The roller 300 can be modified using continuous modification or segmented modification; similarly, the raceway can also be modified using continuous modification or segmented modification. Continuous modification includes circular arc modification, logarithmic curve modification, or other fitted curve modification.

[0062] Taking the modification of the roller 300 as an example, the continuous modification and segmented modification are explained in detail.

[0063] Referring to Figure 6, the roller 300 is continuously modified. The modification of the roller 300 includes modifying the first part 301 and the second part 302 of the roller 300. The modification amount of the second part 302 to the intersection point is different from the modification amount of the first part 301 to the intersection point in both the axial and radial directions, and the modification amount of the second part 302 is greater than the modification amount of the first part 301.

[0064] Specifically, the modification amount of the first part 301 includes the height H1 in the radial direction and the length L1 in the axial direction of the roller 300, and the modification amount of the second part 302 includes the height H2 in the radial direction and the length L2 in the axial direction of the roller 300, wherein the height H2 is greater than the height H1, and the length L2 is greater than the length L1.

[0065] Referring to Figure 7, the roller 300 is modified in a segmented manner, that is, a partially symmetrical and partially asymmetrical modification method. The gap obtained by modification includes symmetrical and asymmetrical regions, and the middle region of the generatrix of the roller 300 may contain straight lines.

[0066] Specifically, the modification of the roller 300 includes modifying the first part 301 and the second part 302. The first part 301 includes a first symmetrical region 3011 and a first asymmetrical region 3012, and the second part 302 includes a second symmetrical region 3021 and a second asymmetrical region 3022. The first symmetrical region 3011 and the second symmetrical region 3021 are symmetrically modified, and the gaps obtained by modification are symmetrical about each other with the intersection point as the center. The first asymmetrical region 3012 and the second asymmetrical region 3022 are asymmetrically modified, and the gaps obtained by modification are asymmetrical about each other with the intersection point as the center. The modification amount of the second asymmetrical region 3022 is greater than the modification amount of the first asymmetrical region 3012.

[0067] In some embodiments, the generatrix of the rollers in the first symmetrical region 3011 and the second symmetrical region 3021 can be a straight line or a curve.

[0068] The modification amount of the first asymmetric region 3012 includes the height H1' in the radial direction and the length L1' in the axial direction of the roller 300. The modification amount of the second asymmetric region 3022 includes the height H2' in the radial direction and the length L2' in the axial direction of the roller 300, wherein the height H2' is greater than the height H1' and the length L2' is greater than the length L1'.

[0069] In another specific embodiment, the modification of the roller bearing is a modification of the raceway. Referring to FIG8, taking the modification of the inner ring raceway 201 as an example, it includes the modification of the inner ring raceway 201 located on one side of the first part 301 of the roller 300 and the modification of the inner ring raceway 201 located on one side of the second part 302. The modification amount of the inner ring raceway 201 located on the second part 302 is greater than the modification amount of the inner ring raceway 201 located on the first part 301.

[0070] Specifically, the modification amount of the inner ring raceway 201 located on one side of the first part 301 includes the height H3 in the radial direction of the roller 300 and the length L3 in the axial direction, and the modification amount of the inner ring raceway 201 located on one side of the second part 302 includes the height H4 in the radial direction of the roller 300 and the length L4 in the axial direction, wherein the height H4 is greater than the height H3 and the length L4 is greater than the length L3.

[0071] In some embodiments, the modification of the raceway also includes modification of the outer raceway 101, or modification of both the inner raceway 201 and the outer raceway 101 simultaneously. The modification of the outer raceway 101 can be specifically referred to in relation to the modification of the inner raceway 201, and will not be repeated here.

[0072] In other embodiments, the modification of the roller bearing can also involve modifying both the roller 300 and the raceway simultaneously. For details, please refer to the modification of the roller and the modification of the inner ring raceway, which will not be repeated here.

[0073] The roller bearing obtained by the above modification method can have the intersection of the radial center plane Y of the roller 300 and the raceway coincide with the center point of the raceway, or the intersection of the radial center plane Y of the roller 300 and the raceway can deviate from the center point of the raceway.

[0074] In another embodiment, the assembly relationship between the roller 300 and the outer ring 100 and the inner ring 200 can be adjusted so that the intersection of the radial center plane Y of the roller 300 and the raceway is offset from the center point of the raceway, thereby achieving that the gap between the roller 300 and the raceway is asymmetrical with respect to the intersection point in the axial direction of the roller 300.

[0075] While the present invention has been disclosed above, it is not limited thereto. Any person skilled in the art can make various modifications and alterations without departing from the spirit and scope of the invention; therefore, the scope of protection of the present invention should be determined by the scope defined in the claims.

Claims

1. A roller bearing, characterized in that, include: Outer ring; An inner ring, which is disposed within the outer ring; A roller is disposed between an inner ring and an outer ring, the inner ring and the outer ring providing raceways for the roller, a gap existing between the roller and the raceways, an intersection point between the radial center plane of the roller and the raceways, and the gap being asymmetrical with respect to the intersection point in the axial direction of the roller.

2. The roller bearing as described in claim 1, characterized in that, The roller includes a first portion and a second portion disposed relative to the radial center plane of the roller, the diameter of the second portion being larger than the diameter of the first portion, the first portion having a first gap with the raceway, and the second portion having a second gap with the raceway, the second gap being larger than the first gap.

3. The roller bearing as described in claim 2, characterized in that, The ratio of the second gap, which is equidistant from the intersection point, to the first gap is less than or equal to 5.

4. The roller bearing as described in claim 2, characterized in that, The gap is formed by modifying the roller, or by modifying the raceway, or by modifying both the roller and the raceway simultaneously.

5. The roller bearing as described in claim 4, characterized in that, The rollers are modified in a segmented or continuous manner; the raceways are modified in a segmented or continuous manner.

6. The roller bearing as described in claim 4, characterized in that, The raceway includes an inner raceway located on the outer circumferential surface of the inner ring and an outer raceway located on the inner circumferential surface of the outer ring; the modification of the raceway includes the modification of the inner raceway and / or the modification of the outer raceway.

7. The roller bearing according to any one of claims 1 to 6, characterized in that, The intersection point coincides with the center point of the raceway, or the intersection point deviates from the center point of the raceway.

8. The roller bearing as claimed in claim 7, characterized in that, When the intersection point deviates from the center point of the raceway, the offset between the intersection point and the center point of the raceway is less than 30% of the raceway length.

9. A method for modifying a roller bearing, characterized in that, include: A roller bearing is provided, the roller bearing including an outer ring, an inner ring and rollers located between the outer ring and the inner ring, the inner ring and the outer ring providing raceways for the rollers, and the radial center plane of the rollers intersecting with the raceways; The rollers of the roller bearing are modified, or the raceways are modified, or both the rollers and the raceways are modified, so that the clearance between the rollers and the raceways is asymmetrical with respect to the intersection point in the axial direction of the rollers.

10. The method for modifying a roller bearing as described in claim 9, characterized in that, The rollers are modified in a segmented or continuous manner; the raceways are modified in a segmented or continuous manner.

11. The method for modifying a roller bearing as described in claim 9, characterized in that, The roller includes a first portion and a second portion disposed relative to the radial center plane of the roller, wherein the diameter of the second portion is larger than the diameter of the first portion.

12. The method for modifying a roller bearing as described in claim 11, characterized in that, When modifying the roller, the modification includes modifying the first part and the second part, wherein the modification amount of the second part is greater than the modification amount of the first part.

13. The method for modifying a roller bearing as described in claim 11, characterized in that, The raceway includes an inner raceway located on the outer circumferential surface of the inner ring and an outer raceway located on the inner circumferential surface of the outer ring.

14. The method for modifying a roller bearing as described in claim 13, characterized in that, When modifying the raceway, the modification includes modifying the inner raceway and / or modifying the outer raceway, wherein the modification amount of the raceway located on the second part side is greater than the modification amount of the raceway located on the first part side.

15. The method for modifying a roller bearing as described in claim 11, characterized in that, When both the roller and the raceway are modified, the sum of the modification amount of the second part and the modification amount of the raceway located on one side of the second part is greater than the sum of the modification amount of the first part and the modification amount of the raceway located on one side of the first part.

16. The method for modifying a roller bearing as described in any one of claims 11 to 15, characterized in that, The first part has a first gap with the raceway, and the second part has a second gap with the raceway, the second gap being larger than the first gap.

17. The method for modifying a roller bearing as described in claim 16, characterized in that, The ratio of the second gap, which is equidistant from the intersection point, to the first gap is less than or equal to 5.

Images