EP3247916A1

EP3247916A1 - Rolling bearing

Info

Publication number: EP3247916A1
Application number: EP15816360.0A
Authority: EP
Inventors: Ernst Masur; Daniel Brehm
Original assignee: Schaeffler Technologies AG and Co KG
Current assignee: Schaeffler Technologies AG and Co KG
Priority date: 2015-01-23
Filing date: 2015-11-17
Publication date: 2017-11-29
Also published as: DE102015201101A1; WO2016116086A1; CN107110214A

Abstract

A rolling bearing (1), having an outer ring (2) with an outer ring raceway (3) and having, arranged axially to the side thereof, at least one rim (4), having an inner ring (8) with an inner ring raceway (9) and having, arranged axially to the side thereof, at least one rim (10), and having rolling bodies (12) which are arranged radially between the outer ring raceway (3) and the inner ring raceway (9) and which are received in a rim-guided cage (11). To realize secure guidance of the cage (11) in the rolling bearing (1), provision is made whereby the cage (11) is composed of a material, the coefficient of thermal expansion of which is greater than the coefficient of thermal expansion of the material of the outer ring (2), of the inner ring (8) and of the rolling bodies (12), and whereby the cage (11) is designed such that, in the cold state of the rolling bearing (1), an inner circumferential surface (11a), which radially faces an outer circumferential surface (10a) of at least one rim (10) of the inner ring (8) and is complementary thereto, of the cage (11) is guided only on said outer circumferential surface (11a) with a small first radial clearance (S1), and such that, in the operationally warm state of the rolling bearing (1), an outer circumferential surface (11b), which faces an inner circumferential surface (4a) of at least one rim (4) of the outer ring (2) and is complementary thereto, of the cage (11) is guided on said inner circumferential surface (4a) of the rim (4) of the outer ring (2) with a small second radial clearance (S2).

Description

Describe

roller bearing

The invention relates to a rolling bearing, comprising an outer ring with an outer raceway and at least one axially laterally disposed board, an inner ring with a Innenringlaufbäh and at least one axially laterally disposed board, as well as arranged radially between the Äußenringlaufbahn and the inner ring raceway, in one board-mounted cage taken rolling elements. Such a rolling position is disclosed in DE 195 30 903 A1. It is a rolling bearing whose rolling elements are guided in a guided on the bearing outer ring, one-piece cage. For Schmäerstoffversorgung is provided to place the contact zone between the cage and bearing outer ring to a diameter range which is greater than the smallest inner diameter of the Wälzkörperlauf ahn in the bearing outer ring.

DE 10 2008 025 788 A1 discloses a Wälziagerkäfig for outboard and inboard roller bearings, with the Wäizköf he holding on Abstan, fixed to Stirntrigem Käfg- webs, the rolling bearing cage Bordbereiche with a maximum Äußendurchmes- or a minimum inner diameter of the roller bearing cage for the support having on each a bearing ring and between the board areas recesses for receiving lubricant.

Rolling bearings, which are heavily loaded by acceleration and vibration, are usually equipped with a board-guided cage, Ma achieved so that de Wälzkörpersatz with cage can be supported on the bearing ring. Support on the outer ring (outboard guide / outer ring guide) as well as on the inner ring (inboard guide / inner ring guide) is possible. The support is generally more effective the larger the Köntäktfläche between cage and bearing ring, If the outer ring, the inner ring and the rolling elements are made of materials that have a substantially the same coefficient of thermal expansion remains the required for e ne leadership of the cage small radial clearance between the cage and the outer ring or the inner ring even when heated substantially »obtained, however, especially with grease lubricated bearings problems with the lubrication of the cage relative to the outer ring or the inner ring occur. This is the case, for example, when all elements of the rolling bearing consist of steel.

Often, however, the cages are made for such bearings of a material having a significantly larger thermal expansion coefficient than that of the bearing rings and the rolling elements, so that either the guide upon heating of the bearing by increasing the radial clearance between the cage and the outer ring or the inner ring is deteriorated or the cage even extends so far that it tends to clamp on the outer ring at operating temperature, especially if there is no adequate lubrication.

Against this background, the invention is the object of the invention to design a rolling bearing of the type mentioned with a board-cage so that both in the cold state of the bearing and in the warm operating condition a perfect guidance of the cage is guaranteed.

This Aufgäbe is solved by a Wälzlage with the features of claim 1, which has an outer ring with an Au ennringiaufbahn and at least one axially laterally disposed board, an inner ring with an inner ring raceway and at least one axially laterally disposed board, as well as radially between the outer ring - Runway and the inner ring track arranged, received in a conveyance guided cage rolling body. In this rolling bearing is provided according to the invention that the cage is made of a material whose coefficient of thermal expansion is greater than the coefficient of thermal expansion of the material of the Au Sen ings, de inner ring and the rolling elements, that the cage is designed so that a Außenum - Fangsfläche at least one Bordes of the inner ring radially opposite, complementary inner peripheral surface of the cage in the cold state of the bearing is guided only at this outer peripheral surface with a slight first radial clearance, and that a Innenumfangsfläche at least one Bordes of the outer ring gegenüberliegen- de, complementary ÄuSenumfangsfläche the cage in the warm operating condition of the bearing is guided on this inner peripheral surface of the rim of the outer ring with a small second radial clearance.

The innenbordföhrung thus acts at relatively low temperatures, so Bel-play, in the range of ~ ^Ö 3NC C to +30 at a Erwä rmu ng of the rolling bearing, the cage expands due to different thermal expansion coefficients, stronger than the other Wilizlagerbestandteile. The cage is designed so that this results in a Äûßenbordführung that either takes over together with the inboard guide the leadership of the cage, or this leadership only takes over. As a result, the cage is guided more accurately under all operating conditions than in the case of known generic roller bearings. The degrees of freedom of the cage are thereby restricted, and cage vibrations are avoided or minimized.

At this point it should be mentioned that unier the term outboard guide a guide of the cage on a rolling in the bearing radially inwardly projecting board of the outer ring, and under Innenbordfübrung a guide the cage on a radially outwardly projecting in the rolling bearing board of the inner ring is understood.

According to an advantageous is provided in this, that the radial Spie! between the outer peripheral surface of the Bordes of the inner ring and the opposite complementary Innenümfangsfläche of the cage and the radial clearance between the inner peripheral surface of the rim of the outer ring and the opposite, complementary Außenausfangsfläche the cage are dimensioned so that the cage in the cold state of the rolling bearing only ah the Oußenumfangsfläch the Bordes of the inner ring is guided, and that the cage is guided in the warm operating condition of the bearing both on the outer circumferential surface of the Bordes of innenri gs and on the inner peripheral surface of the rim of the outer ring.

Since the plastic commonly used for rolling bearings in industrial roller bearings has a larger coefficient of thermal expansion than the outer ring, the inner ring and the Wälzköroer of bearing steel, can be determined by appropriate design of the Cage and the radial clearance between the cage and the Borden de outer ring and the Innenrihgs achieve that a cage is given to the inner ring in the cold state of the bearing, and that in frisky state of the bearing, the radial clearance between the cage and the outer ring so far reduced; that the guidance of the Kifigs also takes place on the outer ring

Both the dimensions of the cage and the choice of the radial clearance between the inner ring and the cage as well as the radial clearance between the outer ring and the cage and the IVIasse de cage in the region of the guides are crucial for the proper management of the cage at all operating temperatures.

To achieve proper lubrication of the guide surfaces of the cage, the inner circumferential groove and / or the outer circumferential surface of the cage may have areas with a maximum outside diameter and a minimum inside diameter for guiding on a rim of the inner ring or outer ring, as well as recesses therebetween Have absorption of lubricant. Such an embodiment of the cage is described in DE 0 2008 025 768 A1, the relevant content of which is here completely made the subject of the disclosure of the invention. The invention will be explained below with reference to a rolling bearing shown in the accompanying drawings welter. in the drawing Est an axial eilschnltt represented by a Erftndurtgsgemäßes rolling bearing 1. It is an angular contact ball bearing, as used for example as a disengagement Jager in a clutch of a motor vehicle. The rolling bearing 1 has an outer ring 2 with an outer ring raceway 3 and a right-hand rim 4 with an inner circumferential surface 4a and a left flange 6. The two rims 4 _S 6 of the outer ring 2 protrude radially and limit the outer ring raceway 3 axially. Axia! On the outside, the two outer ring rims 4, 6 each have annular recesses for receiving and holding a respective sealing ring 5, 7. Concentric with the outer ring s is an inner ring 8 ang o dnet _* which has a fnnenring- runway 9, a right board 10, which has a Äu enumfangsfläche 1öa, and a left board 13. The two inner ring rims 10, 3 protrude radially outwards and bound the inner track 9 axially. Radially arranged between the outer ring 2 and the inner ring 8 are spherical aizkörpef 12, which roll on the outer raceway S and the Innenringiaufbahn 9 as well as by a massive Kunstkälig; 11 are guided.

The cage 1 has a radially inner circumferential surface 1a, which is geometrically complementary to the outer peripheral surface Ida of the right flange 10 of the inner race S and lies radially opposite it. In the cold state of the rolling bearing 1, a first radial gap is created. S1 exists between the outer peripheral surface 10a of the rim 10 of the inner ring 8 and the inner peripheral surface 11a of the cage 11. This first radial clearance S1 is dimensioned such that the cage 11 with the rolling bodies 12 is guided on the outer circumferential surface 10a of the rim 10 on the inner ring 8 without jamming, as is still the case, that a sufficient Sdhmiefung in the cold state of the bearing 1 is guaranteed.

The drawing shows the rolling bearing 1 in the cold state, for example, at -SO ^ C. Accordingly, a zw ites radial clearance S2 between the inner peripheral surface 4a of the right border 4 on the outer ring 2 and the outer peripheral surface 11b on the cage 1 is greater than the first! radial clearance S1 between the outer circumferential surface 10a of the right flange 10 of the inner ring 8 and the inner peripheral surface 11a of the cage 1 shown. When the rolling bearing 1 heats up, the cage 11, which is made as a solid plastic cage, expands more than the outer ring 2, the inner ring 8 and the Wäizkörper 12, this reduces the second radial clearance S2 between the inner peripheral surface 4a of the right Board 4 on the outer ring 2 and the outer peripheral surface 11b on the cage 11 at operating temperature to a value which is the value of the first radial clearance S1 between the Außenumfängsfläche 10a of the right board 10 of the inner ^ around 8 and de inner umfahgsfläche 11a of the cage 11 at kaitem roller bearing 1 corresponds.

Since the cage expands three-dimensionally when heated, by appropriate dimensioning of the first radial clearance S1, the second radial clearance S2 and the mass of the cage 11, the first radial clearance S1 can only be changed or increased insignificantly when heated the second radial clearance S2 at operating temperature reaches a suitable value for guiding the cage 11, which does not result in jamming of the cage 11 on the inner peripheral portion 4a of the first rim 4 on the outer race 2, but remains so great as to provide adequate lubrication is guaranteed.

In addition, the Kunststöffmatenal for the cage 11 itself or by suitable additives schrhierfähige properties that allow precise guidance of the cage 11 with very little second radial play S2,

In order to achieve a perfect lubrication of the radial guide surfaces 1a, 1b of the cage 11, the circumferential surface 11a and / or the outer circumferential surface 1b of the cage 11 can have areas with a maximum outer diameter and a minimum inner diameter for guiding on a rim 4, 10 of the outer ring 2 or of the inner ring 8, and that there are recesses for receiving lubricant. Such an embodiment of the cage is described in DE 10 2008 025 786 AI, the relevant content of which is fully made the subject of the disclosure here; The rolling bearing 1 shown in the drawing is, as already mentioned, designed as an angular contact ball bearing, however, the design principle described is also applicable to Rienku- geilagern, ZyJnderroHeniagem or Kegeiroilenlagem to make the leadership of the cage 11 according to the Erfi tion. All the features mentioned in the preceding description of the figures, in the claims and in the introduction to the description are both individually and in any combination. r foh einseföbar together. The invention is thus not limited to the described and claimed Merkmafskambinationen, but all e kmaisköm are ha- tioneh to be regarded as disclosed.

ÖezugzeschenUste

I rolling bearings

outer ring

3 outer ringlaufbah.fi

4 Right board

4a Innenumfangsfliche on board 4

5 sealing ring

6 LiekerBörd

7 sealing ring

8 I nessring

9 inner ring raceway

10 Right board on the inner ring

10a. Extensive surface of the board 1 Ö

I I cage

11a Inner surface of the cage

11 Exterior of the cage

12 VVfek body

13 Left board at Inring

First radial play between the outer circumference 1 1a and inner 11a

52 Second radial clearance between inner race surface 4a and outer peripheral surface 1b

Claims

claims

1. rolling bearing (1), comprising an outer ring (2) with an outer ring raceway (3) and at least one axiai laterally arranged board (4).

an inner ring (8) with a innenringiaufbähn (9) and at least one axially laterally arranged board (10),

sowi with radially between the Äußßenringiaufbahn (3) and the innenringiaufbähn (9) arranged in an on-board cage {11) aufgenömn prefeed bodies (12), dadurc characterized,

that the cage (11) consists of a material whose thermal expansion coefficient is greater than the coefficient of thermal expansion of the material of the outer ring ^ 2}, the inner ring (8) and the WäSzkörper (12),

in that the cage (11) is designed in such a way that a complementary inner circumferential surface (11a) of the cage (11), radially opposite an outer circumferential surface (10a) of at least one rim (10) of the annular ring (8), is in the cold state of the rolling bearing (1 ) is only honed on said outer peripheral surface (11a) with a slight first radial clearance, and in that a complementary outer peripheral surface (1b) of the cage (1b) opposite at least one rim (4) of the outer ring (2) 11) in the warm operating condition of the rolling bearing (1) on this inner urnfangsfläche (4a) of the board (4) of the outer ring (2) with a low second radiaien Sp e! (S2) is guided.

2. Wiklager according to claim 1, characterized in that the first radial Spie! (S1) between the outer peripheral surface (10a) of the rim (10 of the inner ring (8 and the opposite, complementary inner peripheral surface (a) of the cage (11)

and the second radial clearance (S2) between the inner peripheral fulcrum (4a) of the rim (4) of the outer ring (2) and the superior, complementary outer peripheral surface (II) of the cage (11) are dimensioned

that the cage (11) in the cold state of the roller bearing (1) is guided only on the outer circumferential surface (tOa) of the rim (10) of the inner ring (8), and that the cage (1t) i operating warm state of the rolling bearing (1) both on the outer peripheral surface (10a) of the rim (10) of the inner ring (8) and the Snnen- circumferential surface (4a) of the rim (4) of the outer ring ( 2) is guided,

3. Rolling bearing according to claim 1 or 2, dadu c gekennzeichne that the cage (11) is made as a solid cage made of plastic, and that the outer ring (2) _f fnnenring the ring (8} and the rolling elements (12) are made of rolling bearing steel.

4. Rolling bearing according to one of claims 1 to 3, characterized in that the inner nenfangfangfläche (11 a) and / or the Umumufahgfläehe (11 b) of the cage (11) areas with a maximum outer diameter and ei em minimum inner diameter for guiding on a rim (4, 1D) of the outer ring (2) or the inner ring (8), and that umiaogsbezogen between these areas recesses for receiving lubricant are present,