ROLLER CAGE ASSEMBLY AND ROTATING GUIDE BEARING COMPRISING AT LEAST ONE SUCH ASSEMBLY

Abstract

The present invention relates to a roller cage assembly (200S) for guiding the rotation of a first bearing ring relative to a second bearing ring, comprising a series of rollers (RS), each having an individual axis of rotation (AS), and a cage (10S) for guiding and positioning the rollers (RS). The cage (10S) comprises at least one ring or ring segment (12SA, 12SB) which includes a series of circumferentially distributed fingers (14SA, 14SB), each of which is received inside an axial hole in an associated roller (RS). The invention is characterized in that the ring or ring segment (12SA, 12SB) and the series of fingers (14SA, 14SB) are made in one piece. The invention also provides a bearing incorporating at least one roller cage assembly. Figure for the abstract: 6

Description

Title of the invention: ROLLER CAGE ASSEMBLY AND ROTATING GUIDE BEARING COMPRISING AT LEAST ONE SUCH ASSEMBLY Technical field of the invention

[0001] The invention relates to a roller cage assembly for guiding in rotation, around a main axis of rotation, a first bearing ring relative to a second bearing ring.

[0002] The invention also relates to a rotational guide bearing suitable for being interposed between two elements of a structure that are mounted to rotate relative to each other. Technical background

[0003] The invention relates to a roller cage assembly for guiding the rotation, around a main axis of rotation, of a first bearing ring relative to a second bearing ring, this assembly comprising: - a series of rollers, each having its own axis of rotation, and which are distributed circumferentially around the main axis; and - and a cage for guiding and circumferentially positioning the rollers.

[0004] By way of example, one or more cages can be integrated into a rotating guide bearing, or bearing.

[0005] Examples of integration of three roller cages are illustrated for example in documents FR2072552 and EP2503164B1.

[0006] The guidance of the rollers is very important in order to avoid any contact between the rollers, which would lead to their wear and premature failure, and to maintain the axis of rotation of each of the rollers in the optimal position, in order to avoid an increase in torque and premature failure.

[0007] A first problem with this standard guidance is that the number of rollers is limited by the thickness of the cage wall between adjacent rollers.

[0008] In a known manner, cages, or segments of cages, can be used in which the cage has a series of windows in each of which a roller is arranged with play.

[0009] The angular or circumferential gap between the rollers must be large enough to maintain sufficient resistance of the cage wall between the rollers of the same sector, and between the rollers of two neighboring sectors.

[0010] The space between the cage segments must also be sufficient to avoid blockages due to expansion under the effect of heat in particular.

[0011] This limits the number of rollers and therefore the load capacity of the bearing.

[0012] A second problem is that the standard guidance from the outside diameter of the rollers leads to the removal of lubricant on the outside diameter of the roller, and thus limits the amount of lubricant present at the contact surfaces between the rollers and the tracks or bearing surfaces.

[0013] This can cause premature wear during operation.

[0014] A third problem is that conventionally designed cages have a large volume and that, most of the time, there is contact between the cages and the raceways, which limits the circulation of lubricant inside the bearing and thus prevents uniform lubrication of the bearing.

[0015] One of the known solutions consists of guiding the rollers by using a design in which the cage includes at least one ring which has a series of circumferentially distributed fingers, each of which is received inside an axial hole of an associated roller.

[0016] An example of such a design is illustrated in document EP2172664A1. This design, which involves making such fingers in the form of pins screwed into two complementary rings, is complex, expensive, heavy, and difficult to assemble and integrate into bearing structures.

[0017] In general, it is also desirable to be able to reduce the weight and manufacturing cost of the rollers and cages. Summary of the invention

[0018] The invention proposes a roller cage assembly for guiding the rotation, around a main axis of rotation, of a first bearing ring relative to a second bearing ring comprising: - a series of rollers, each having an individual axis of rotation, and which are distributed circumferentially around the main axis; - and a cage for guiding and circumferentially positioning the rollers around the main axis, in which the cage comprises at least one ring or ring segment which has a series of circumferentially distributed fingers, each of which is received inside an axial hole of an associated roller, characterized in that the ring and the series of fingers are made in one piece.

[0019] According to other features of the invention:

[0020] - the cage comprises two complementary rings or ring segments of which Each comprises a series of fingers, made in one piece with the ring or ring segment, which are distributed circumferentially and each of which is received inside an axial hole of an associated roller; and each roller, at least one of its two opposite axial ends, has an axial hole which receives a finger of one of the two complementary rings or ring segments; - the individual axis of rotation of each roller is orthogonal to the main axis of rotation; - the individual axis of rotation of each roller is parallel to the main axis of rotation;

[0021] - the individual axis of rotation of each roller forms an angle including between 0 and 90 degrees of angle with respect to the main axis of rotation; - each ring or ring segment with its fingers is in the shape of a leaf, flat or curved; - each ring or ring segment with its fingers is made by cutting, in particular by laser cutting, from a sheet of metal;

[0022] - each ring or ring segment with its fingers is provided with a coating promoting sliding, and therefore limiting wear - at each of its two opposite ends, each roller has a blind axial hole which is suitable for receiving a finger; - each roller has a through axial hole, each axial end of which is suitable for receiving a finger; - each roller is a cylindrical roller or of a similar shape; - each roller is a conical, truncated conical, or similarly shaped roller - each roll is made by cutting a section of tube or solid bar; - the two complementary rings or ring segments of the cage are joined to each other; - the two rings or ring segments of the cage are independent of each other; - that the end sections of two aligned and opposite fingers received inside the same roller overlap axially; - each cage extends along a determined angular sector and / or is made up of several independent angular sectors.

[0023] The invention also proposes a rotational guide bearing, about a main axis of rotation, suitable for being interposed between two elements of a structure that are mounted to rotate relative to each other, this bearing comprising: - a first bearing ring, radially inner; - a second coaxial bearing ring, radially external, extending around the first bearing ring; - and at least one assembly for guiding the rotation of the first bearing ring relative to the second bearing ring made according to the invention.

[0024] According to other bearing characteristics: - one of the two bearing rings has a housing open radially with respect to the main axis of rotation; the other of the two bearing rings has a projecting part which extends radially inside the housing, and it has at least two assemblies for guiding the rotation of the first bearing ring with respect to the second bearing ring, each of which is made according to the invention and which has two assemblies in each of which the individual axis of rotation of each roller forms a non-zero angle with respect to the main axis of rotation and each of which is axially interposed between two opposite annular bearing tracks belonging respectively to the projecting part and to the housing; - the protruding part extends radially towards the main axis of rotation from the second radially outer bearing ring; - the protruding part extends radially in the opposite direction to the main axis of rotation from the first radially inner bearing ring. Brief description of the figures

[0025] Other features and advantages of the invention will become apparent upon reading the detailed description that follows, for an understanding of which reference should be made to the accompanying drawings in which:

[0026] [Fig-1] - [Fig.1] is a cross-sectional view through an axial plane of an assembly comprising a guide bearing incorporating three sets of roller cages;

[0027] [Fig.2] - [Fig.2] is a partial cross-sectional and perspective view of the assembly of [Fig.1];

[0028] [Fig.3] - [Fig.3] is a partial cross-sectional and perspective view similar to that of [Fig.2] on which only the three roller cage assemblies are shown;

[0029] [Fig.4] - [Fig.4] is an exploded perspective detail view of a section of the central roller cage assembly;

[0030] [Fig.5] - the [Fig.5] is a perspective view of a section of one of the two upper or lower roller cage assemblies;

[0031] [Fig.6] - [Fig.6] is an exploded perspective view of the section illustrated in [Fig.4];

[0032] [Fig.7] - [Fig.7] is a cross-sectional view by plane 7-7 of [Fig.5];

[0033] [Fig.8] - [Fig.8] is a view analogous to that of [Fig.5] illustrating a variant of construction of the cage illustrated in figures 5 to 7. Detailed description of the invention

[0034] For the description of the invention and the understanding of the claims, the vertical orientation along the orientation of the principal axis of rotation AP indicated in [Fig.1] will be adopted without limitation and without limiting reference to terrestrial gravity.

[0035] In the description that follows, identical, similar or analogous elements will be designated by the same reference numerals or by analogous and indexed reference numerals.

[0036] In [Fig. 1], in section by an axial plane passing through a principal axis of rotation AP, an assembly 100 comprising a ring or bearing 106 for guiding the rotation of an upper component 102 relative to a lower component 104 is shown.

[0037] The two components 102 and 104 are, for example, the lower end of a wind turbine blade pivotally assembled on a rotor hub 104.

[0038] The bearing 106 includes a first bearing ring 108 - radially internal with respect to the main axis AP - in two upper and lower parts 110 - on which the component 102 is fixed.

[0039] The assembly of the three components 102, 110 and 112 is achieved by means of a set of axial bolts 114 distributed circumferentially around the main axis AP.

[0040] The first bearing ring 108 has a housing 116 which is open radially, here outwards, with respect to the main axis of rotation.

[0041] The housing 116 of the bearing ring 108 is formed partly in the lower part 112 and partly in the upper part 110 and is delimited vertically by two flat and opposite annular faces orthogonal to the main axis AP, of which an upper face 122 and a lower face 123.

[0042] Each flat annular face 122, 123 constitutes a flat annular rolling track belonging to the first rolling ring 108.

[0043] The housing 116 is also delimited, radially inwards by a convex cylindrical face of axial orientation 118.

[0044] The face 118 constitutes a cylindrical bearing track belonging to the first bearing ring 108.

[0045] The bearing 106 includes a second bearing ring 124 - radially external with respect to the main axis AP - in one part on which the component 104 is fixed.

[0046] The assembly of the two components 104 and 124 is achieved by means of a set of axial bolts 126 distributed circumferentially around the main axis AP.

[0047] The second bearing ring 124 has a projecting part 128 which here extends radially towards the main axis AP inside the housing 116 of the first bearing ring 108.

[0048] The projecting part, or nose, 128 is delimited vertically by two flat and opposite annular faces orthogonal to the main axis AP, of which a superior face 132 and a inferior face 133.

[0049] Each flat annular face 132, 133 constitutes a flat annular rolling track belonging to the second rolling ring 124.

[0050] The projecting part 128 is also delimited, radially inwards by a concave cylindrical face of axial orientation 130.

[0051] The face 130 constitutes a cylindrical bearing track belonging to the second bearing ring 124.

[0052] The projecting part 128 extends radially inwards from a concave axial cylindrical surface 129 of the body of the second bearing ring 124.

[0053] An upper roller cage assembly 200S is interposed axially between the flat and parallel annular bearing tracks 122 and 132, while a lower roller cage assembly 2001 is interposed axially between the annular and opposite tracks 123 and 133.

[0054] The rotation axes AS and AI of the rollers of the two roller cage assemblies 200S and 2001 are orthogonal to the main rotation axis AP.

[0055] The two roller cage assemblies 200S and 2001 of the bearing 106 are suitable for supporting axial loads oriented parallel to the main axis AP.

[0056] By way of non-limitation, the design of the two roller cage assemblies 200S and 2001 of bearing 106 is identical here.

[0057] A central roller cage assembly 200C is radially interposed between the parallel cylindrical bearing tracks 118 and 130.

[0058] The rotation axes of the rollers of the central roller cage assembly 200C are parallel to the main rotation axis AP.

[0059] The central 200C roller cage assembly is suitable for supporting radial loads oriented orthogonally to the main axis AP.

[0060] Traditionally, each series of rollers belonging to a 200S, 2001 or 200C roller cage is arranged in a circle angularly around the main axis AP.

[0061] With reference in particular to figures 3 and 4, we will now describe the example design of the central 200C roller cage assembly.

[0062] The assembly 200C comprises a series of RC rollers, each having an individual axis of rotation AC, and which are distributed circumferentially around the main axis AP.

[0063] To guide and position the RC rollers, the assembly 200C here includes a cage 10C, for guiding and circumferentially positioning the RC rollers, in two complementary parts 10CA and 10CB (See [Fig.4]) each of which includes a ring 12CA, 12CB.

[0064] Each ring 12CA, 12CB has a series of fingers 14CA, 14CB which are distributed circumferentially along the ring 12CA, 12CB.

[0065] Each ring, or ring sector ,12CA, 12CB is made in one piece with its series of associated fingers.

[0066] By way of non-limiting information, each ring 12CA, 12CB is in the shape of a sheet or plate which is here curved to adopt an overall cylindrical conformation.

[0067] By way of non-limitation, each RC roller has a through axial hole 16C which opens at the two opposite axial ends of the RC roller.

[0068] Each finger 14CA, 14CB is received inside an axial hole 16C of an associated RC roller.

[0069] The design of each of the two upper roller cage assemblies 200S and 2001 is identical here.

[0070] With reference in particular to figures 3, and 5 to 7, we will now describe in more detail the example design of the upper assembly 200S of roller cage.

[0071] The 200S assembly comprises a series of RS rollers, each having an individual axis of rotation AS, which are distributed circumferentially around the main axis AP.

[0072] To guide and position the RS rollers, the assembly 200S here includes a cage 10S for circumferential guidance and positioning of the RS rollers, in two complementary parts 10SA and 10SB, each of which includes a ring 12SA, 12SB.

[0073] Each 12SA, 12SB ring has a series of 14SA, 14SB fingers which are distributed circumferentially along the 12SA, 12SB ring.

[0074] Each ring, or ring sector, 12SA, is made in one piece with its series of associated fingers.

[0075] By way of non-limitation, each 12SA, 12SB ring is in the shape of a flat annular sheet or plate.

[0076] By way of non-limitation, each RS roller has a through axial hole 16S which opens at the two opposite axial ends of the RS roller.

[0077] Each finger 14SA, 14SB is received inside an axial hole 16S of an associated RS roller.

[0078] The corresponding components of assembly 2001 are designated by the same alphanumeric references indexed "I", namely RI, AI, 101, 12IA, 12IB, 14IA, 14IB, 161.

[0079] According to one embodiment, each ring 12CA, 12CB, 12SA, 12SB, 12IA, 12IB with its fingers 14CA, 14CB, 14SA, 14SB, 14IA, 14IB is made by cutting, in particular by laser cutting, in a sheet of metal.

[0080] By way of non-limiting example, each finger 14CA, 14CB, 14SA, 14SB, 14IA, 14IB here presents a rectangular section.

[0081] It is thus possible to produce metal cages at reduced cost by laser cutting from a standard sheet of construction steel. Then, a polyamide (PA) coating similar to that used for coating ball bearing cages can be applied; for example, a PA11 or PA12 polyamide which can be deposited by immersion in a fluidized bath.

[0082] Such a method of production is in particular more economical than the production of molded plastic cages which requires in particular the manufacture of as many molds as necessary.

[0083] Alternatively, the fingers may have a circular cross-section requiring the implementation of other manufacturing techniques, or additional manufacturing steps.

[0084] By way of non-limitation, according to one embodiment, when each roller RC, RS, RI is a cylindrical roller of substantially constant section and has a through axial hole 16C, 16S, 161 (each axial end of which is suitable for receiving a finger 14CA, 14CB, 14SA, 14SB, 14IA, 14IB), each cylindrical roller can be made by cutting a section of tube.

[0085] The ability to produce large diameter axial holes 16C, 16S, 161 makes it possible to significantly reduce the weight of the rollers, which are made from an expensive material, and to produce these rollers from tubes rather than solid bars to reduce weight and costs.

[0086] The maximum diameter of the hole is defined according to the minimum load capacity of the roller.

[0087] When, in particular due to the desired load level or a reduced outer diameter of the roller, the design of a roller with a through axial hole is not possible, the other advantages of the innovative cage design remain applicable by, for example, using a roller which has a blind axial hole at each of its two opposite axial ends which is suitable for receiving an associated finger.

[0088] Reduced cost and reduced weight are not the only advantages of this design, as it is also more reliable than conventional plastic cages with windows currently in use.

[0089] Indeed, steel cages are much stronger and less fragile than plastic cages.

[0090] For the assembly and mounting of each roller cage assembly, the following procedure is used for example.

[0091] Considering figures 5 to 7, the fingers 14SA of the radially inner ring 10SA are introduced through the four axial holes 16S of the rollers RS, and then the fingers 14SB of the radially outer ring 12SB are introduced into the axial holes 16S of the rollers RS.

[0092] Next, the "pre-assembled" 200S assembly can be placed in position inside the bearing 106 between the bearing rings 108 and 124.

[0093] According to the variant illustrated in [Fig.8], the two complementary rings 12SA and 12SB can be joined together.

[0094] For this purpose, by way of example, the free end sections of two aligned and opposite fingers 14SA and 14SB received inside the same roller RS ​​overlap axially and are fixed to each other.

[0095] In the sense of the invention, each roller cage assembly can be made in the form of a complete annular assembly extending over 360°, or in the form of a roller cage segment extending over an arc of a circle, several segments being able to be associated along a circumference.

[0096] Depending on the applications, a complete or segmental roller cage assembly may consist of only one ring or one ring segment with its fingers which are received in the series of associated rollers.

[0097] It is also possible to leave fingers without rollers, the number of rollers equipping a cage being able to be determined in particular according to the loads to be borne.

[0098] An assembly according to the invention may comprise only one lateral roller guide cage (in one piece or in several segments) arranged on only one side of the rollers. In such a case, a single perforated end of each roller is sufficient.

[0099] In the sense of the invention, each cylindrical roller can have a profile approaching that of a cylinder with a straight generatrix (As illustrated in the figures) and in particular have a barrel or convex profile.

[0100] The invention can also be applied to assemblies comprising conical or truncated conical rollers.

[0101] Each roller can also be made from a section of a solid bar. In this case, the end hole(s) can be made by drilling.

[0102] The rollers of a series can roll on the surface of an associated track or be received in a groove cut into this surface.

[0103] Each bearing ring can be made in one or more parts.

[0104] The invention also applies to a bearing comprising, for example, only two opposing assemblies similar to the 200S and 2001 assemblies described above, which are received between opposing annular trunconical rolling tracks, each forming an angle with respect to the main axis of rotation.

[0105] The invention is applicable to the design of all types of bearings or housings, including linear guides for movement suitable for interposed between two structural elements that are mounted to move relative to each other, this housing comprising a first bearing element, made in one or more parts, a second bearing element, made in one or more parts, extending parallel to the first bearing element, and at least one assembly for guiding the first bearing element relative to the second bearing element. carried out according to the principle of the invention and in which there is a cage for guiding and circumferentially positioning the rollers around said main axis, in which the cage comprises at least one straight segment which comprises a series of linearly distributed fingers, each of which is received inside an axial hole of a roller, each straight segment and the series of fingers being made in one piece.

Claims

Demands

1. Bearing (106) for rotational guidance about a main axis (AP) of rotation, suitable for being interposed between two elements (102, 104) of a structure which are mounted to rotate relative to each other, this bearing (106) comprising: - a first bearing ring (108), radially internal, made in one or more parts; - a second coaxial bearing ring (124), radially external, made in one or more parts, extending around the first bearing ring (108); - and three sets (200C, 2001, 200S) of roller cage for guiding the rotation of the first bearing ring (108) relative to the second bearing ring (124), characterized: - in that each said set (200C, 2001, 200S) comprises: - - a series of rollers (RC, RS, RI) each having an individual axis of rotation (AC, AS, AI) and which are distributed circumferentially around said main axis (AP);- - and a cage (10C, 10S, 101) for guiding and circumferentially positioning the rollers (RC, RS, RI) around said main axis (AP), - and in that said cage (10C, 10S, 101) of each said assembly comprises at least one ring or ring segment (12CA, 12CB, 12SA, 12CB, 12IA, 12IB): - - which comprises a series of circumferentially distributed fingers (14CA, 14CB, 14SA, 14Sb, 14IA, 14IB), each of which is received inside an axial hole of an associated roller (RC, RS, RI); - - which, together with the series of associated fingers (14CA, 14CB, 14SA, 14Sb, 14IA, 14IB), are made in one piece.;

2. Bearing (106) according to claim 1, characterized in that: - each cage (10C, 10S, 101) comprises two complementary rings or ring segments (12CA, 12CB, 12SA, 12CB, 12IA, 12IB), each of which comprises a series of fingers (14CA, 14CB, 14SA, 14Sb, 14IA, 14IB), made in one piece with the ring or ring segment (12CA, 12CB, 12SA, 12CB, 12IA, 12IB), which are distributed circumferentially and each of which is received inside an axial hole (16) of an associated roller (RC, RS, RI); and - each roller (RC, RS, RI), at each of its two opposite axial ends, has an axial hole (16C, 16S, 161) which receives a finger (14C, 14S, 141) of one of the two complementary rings or ring segments (12CA, 12CB, 12SA, 12CB, 12IA, 12IB).

3. Bearing (106) according to claim 1 or 2, characterized: - in that it comprises two sets (2001, 200S) of roller cage for the rotational guidance of the first bearing ring (108) relative to the second bearing ring (124); - and in that, for each of said two sets (2001, 200S), the individual axis (AS, AI) of rotation of each roller (RS, RI) is orthogonal to said main axis (AP) of rotation.

4. Bearing (106) according to any one of claims 1 or 2, characterized in that it comprises a roller cage assembly (200C) for guiding the rotation of the first bearing ring (108) relative to the second bearing ring (124) the individual axis (AC) of rotation of each roller (RC) of which is parallel to said main axis (AP) of rotation.

5. Bearing (106) according to claim 4 taken in combination with claim 3, characterized in that: - said two assemblies (200S, 2001) comprise an upper assembly (200S) of roller cage which is axially interposed between flat and parallel annular raceways (122 and 132) of bearing and a lower assembly (2001) of roller cage is axially interposed between annular and parallel raceways (123 and 133); - said one assembly (200C) of roller cage is a central assembly (200C) of roller cage which is radially interposed between cylindrical and parallel raceways (118 and 130).

6. Bearing (106) according to any one of the preceding claims, characterized in that each ring or ring segment (12CA, 12CB, 12SA, 12CB, 12IA, 12IB) with its associated fingers (14CA, 14CB, 14SA, 14Sb, 14IA, 14IB) is in the shape of a sheet, flat or curved.

7. Bearing (106) according to the preceding claim, characterized in that each ring or ring segment (12CA, 12CB, 12SA, 12CB, 12IA, 12IB) with its associated fingers (14CA, 14CB, 14SA, 14Sb, 14IA, 14IB) is made by cutting, in particular by laser cutting, in a sheet of metal.

8. Bearing (106) according to any one of the preceding claims, characterized in that, at at least one of its two opposite ends, each roller (RC, RS, RI) has a blind axial hole (16C, 16S, 161) which is suitable for receiving a finger.

9. Bearing (106) (200C, 2001, 200S) according to any one of claims 1 to 8, characterized in that each roller (RC, RS, RI) has a through axial hole (16C, 16S, 161) of which each axial end is suitable for receiving a finger.

10. Bearing (106) according to claim 9, characterized in that each roller (RC, RS, RI) is made by cutting a section of tube.

11. Bearing (106) according to claim 9, characterized in that the two rings or ring segments (12CA, 12CB, 12SA, 12CB, 12IA, 12IB) complementary to the cage (10C, 10S, 101) are fixed to each other.

12. Bearing (106) according to claim 9, characterized in that the two rings or ring segments (12CA, 12CB, 12SA, 12CB, 12IA, 12IB) of the cage (10C, 10S, 101) are independent of each other.

13. Bearing (106) according to claim 9, characterized in that the free end sections of two aligned and opposite fingers (14CA, 14CB, 14SA, 14Sb, 14IA, 14IB) received inside the same roller (RC, RS, RI) overlap axially.

14. Bearing (106) according to any one of the preceding claims, characterized in that each cage (10C, 10S, 101) extends along a determined angular sector and / or is made up of several independent angular sectors.

15. Bearing (106) according to claim 3 or 5, characterized in that: - one (108) of the two bearing rings comprises a housing (116) open radially with respect to the main axis (AP) of rotation; - the other (124) of the two bearing rings comprises a projecting portion (128) extending radially inside said housing (116), and in that each of said two assemblies (2001, 200S) for guiding the rotation of the first bearing ring (108) with respect to the second bearing ring (124) is axially interposed between two opposite annular bearing tracks (132-133, 122-123) belonging respectively to said protruding part (128) and said housing (116).

16. Bearing (106) according to the preceding claim, characterized in that said projecting part extends radially opposite the main axis of rotation from the first radially inner bearing ring (108).

17. Bearing (106) according to claim 15, characterized in that said projecting part (128) extends radially towards the main axis of rotation (AP) from the second radially outer bearing ring (124).

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