Sleeve for deep groove ball bearing

A deep groove ball bearing assembly is disclosed. The assembly includes an inner bearing ring defining an inner race, an outer bearing ring defining an outer race, and a plurality of rolling elements supported on the inner race and the outer race. A shaft is supported on a radially inner surface of the inner bearing ring, and a housing is supported on a radially outer surface of the outer bearing ring. A sleeve is arranged between the radially outer surface of the outer bearing ring and a radially inner surface of the housing, and the sleeve includes a plurality of through openings.

FIELD OF INVENTION

The present invention relates to a deep groove ball bearing.

BACKGROUND

Deep groove ball bearings are well known, particularly in the automotive field. Deep groove ball bearings are used in automotive transmissions, especially for continuously variable transmissions or hybrid transmission or e-axles. These known types of bearings experience creep due to high speed and heavy loads. In particular, the outer bearing ring experiences creep, which causes fretting and wear in the outer housing, typically formed from aluminum. Known solutions for addressing bearing creep include applying a coating to the bearing components, or require the use of an angular contact bearing with a biasing element to provide a preload. These solutions are relatively expensive and require additional assembly steps and handling.

Known solutions for addressing creep or thermal expansion of bearing assemblies are disclosed in US Pub 2012/0093453; U.S. Pat. Nos. 8,684,608; 5,028,152; and US Pub. 2009/0080824.

It would be desirable to provide a cost-effective solution for addressing fretting and wear in deep groove ball bearings that does not affect load capacity and is relatively simple to assemble.

SUMMARY

A deep groove ball bearing assembly including a sleeve to prevent fretting and wear is disclosed. The assembly includes an inner bearing ring defining an inner race, an outer bearing ring defining an outer race, and a plurality of rolling elements supported on the inner race and the outer race. A shaft is supported on a radially inner surface of the inner bearing ring, and a housing is supported on a radially outer surface of the outer bearing ring. The sleeve is arranged between the radially outer surface of the outer bearing ring and a radially inner surface of the housing, and the sleeve includes a plurality of through openings.

The sleeve alters a contact interface between the housing and the outer bearing ring to reduce or eliminate creep.

The sleeve can either be a split ring or a closed ring.

The sleeve can be formed as a deep-drawn stamped component.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Certain terminology is used in the following description for convenience only and is not limiting. The words “front,” “rear,” “upper” and “lower” designate directions in the drawings to which reference is made. The words “inwardly” and “outwardly” refer to directions toward and away from the parts referenced in the drawings. “Axially” refers to a direction along the axis of a shaft. A reference to a list of items that are cited as “at least one of a, b, or c” (where a, b, and c represent the items being listed) means any single one of the items a, b, or c, or combinations thereof. The terminology includes the words specifically noted above, derivatives thereof and words of similar import.

As shown inFIG. 1A, a deep groove ball bearing assembly10is disclosed. The assembly10includes an inner bearing ring12defining an inner race13, an outer bearing ring14defining an outer race15, and a plurality of rolling elements16supported on the inner race13and the outer race15. In one embodiment, the rolling elements16are spherical rolling elements. In one embodiment, the rolling elements16are supported by a cage17. One of ordinary skill in the art would understand that the rolling elements16can be modified according to a particular application. One of ordinary skill in the art would also understand that the cage17can be omitted. A shaft18is supported on a radially inner surface of the inner bearing ring12, and a housing20is supported on a radially outer surface19of the outer bearing ring14. In one embodiment, the housing20is formed from aluminum, while the bearing rings1214are formed from bearing grade steel.

A sleeve30, shown in various views in greater detail inFIGS. 1C-1F, is arranged between the radially outer surface19of the outer bearing ring and a radially inner surface21of the housing20. The sleeve30includes a plurality of through openings32. In one embodiment, the through openings32are spaced along an entire circumferential extent of the sleeve30. In one embodiment, there are at least fourteen through openings32. In one embodiment, the sleeve30is a closed ring, i.e. the sleeve30extends circumferentially for 360 degrees. One of ordinary skill in the art would understand that the exact configuration of the through openings32can be varied.

In one embodiment, the sleeve30is a deep-drawn stamped sleeve. The sleeve30is preferably formed from sheet metal. In one embodiment, the sleeve30is wrapped around a respective contact surface of the assembly10and then welded closed. The sleeve30can also be heat treated to provide increased strength. In one embodiment, the sleeve30has a thickness of 0.1 mm-1.0 mm. One of ordinary skill in the art would understand that the thickness of the sleeve30can be varied depending on a specific application.

In one embodiment, each through opening32includes a pair of circumferentially extending slots34a,34bconnected by an axially extending slot34c. As shown most clearly inFIG. 1E, the through opening32has a generally H-shaped profile.

In one embodiment, the sleeve30includes a plurality of grooves36a,36b,38a,38b. The plurality of grooves36a,36b,38a,38bcan include a first plurality of grooves36a,36bextending circumferentially to connect adjacent through openings32, and a second plurality of grooves38a,38bextending axially to connect axially outermost edges of the sleeve39a,39band the plurality of through openings32. As used herein, the term “groove” is understood to not completely extend through the sleeve30, in contrast to the through openings32. A depth of the grooves can be varied to optimize lubrication of the contact surfaces of the bearing components. The grooves36a,36b,38a,38bprovide lubrication conduits for directing lubrication to contact surfaces of the housing20and the outer bearing ring14.

As shown inFIG. 1B, the sleeve30has an axial extent (dl) that extends a majority of the contact surfaces defined by the housing20and the outer bearing ring14. More preferably, the sleeve30extends at least 90% of a contact surface defined by the outer bearing ring14.

As shown inFIGS. 1D and 1G, a plurality of tabs35a,35bare defined by the sleeve30. The tabs35a,35bare defined in an axially medial region of the sleeve30between adjacent pairs of the through openings32. The tabs35a,35bcan have a bent configuration relative to a circumferential direction, as best shown inFIG. 1D, to provide a biasing force. As shown in the drawings, the tabs35a,35bare bent radially outwardly. This configuration ensures proper contact of the sleeve30with the corresponding contact surfaces regardless of any thermal expansion of the housing20.

In one embodiment, the sleeve30is press fit onto the outer bearing ring14and has a slip-fit relative to the housing20. One of ordinary skill in the art would understand that various fits could be used to install the sleeve30between the outer bearing ring14and housing20.

In one embodiment, the through openings32define a first area that is at least 15% of a total area of the sleeve30. In one embodiment, the first area is 15%-33% of the total area of the sleeve30. One of ordinary skill in the art would understand that the area of the through openings32can be varied depending on specific requirements for a particular application.

In another embodiment, shown inFIGS. 2A-2C, the sleeve130is a split ring, i.e. the sleeve30does not extend circumferentially for an entire 360 degrees. As shown inFIGS. 2A-2C, the sleeve130defines a split140. The split140provides an alternative configuration in which the sleeve130does not need to be welded closed during installation, thereby simplifying installation.

The sleeve30generally provides the following advantages. The sleeve30reduces or completely stops creep of the outer bearing ring14. The sleeve30also reduces housing20fretting and wear. In addition to preventing creep, the sleeve30provides an improved lubrication configuration due to the through openings32and grooves36a,36b,38a,38b, which help reduce fretting and wear. The relatively thin profile of the sleeve30also does not increase installation space.

Having thus described the present invention in detail, it is to be appreciated and will be apparent to those skilled in the art that many physical changes, only a few of which are exemplified in the detailed description of the invention, could be made without altering the inventive concepts and principles embodied therein. It is also to be appreciated that numerous embodiments incorporating only part of the preferred embodiment are possible which do not alter, with respect to those parts, the inventive concepts and principles embodied therein. The present embodiment and optional configurations are therefore to be considered in all respects as exemplary and/or illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all alternate embodiments and changes to this embodiment which come within the meaning and range of equivalency of said claims are therefore to be embraced therein.

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