Light duty bearing assembly

A method for mounting a light duty bearing having a groove defined in an outer arcuate surface thereof for receiving a metallic tolerance ring placed therein which includes protruding waves extending radially outwardly from the groove while the main band of the bearing is positioned preferably completely within the groove such that the bearing can be placed into a workpiece aperture to be movably mounted therein in a frictionally resisted manner such as required in light-duty applications where slight restricted movement between the bearing and the mounting aperture of the workpiece is desirable. The bearing assembly can be mounted in the workpiece aperture by exerting axial force against the inner race member or the outer race member to achieve the frictionally resisted mounting therebetween. The groove defined in the outer portion of the bearing is designed to receive and retain the tolerance ring therein during mounting in the workpiece aperture for greatly facilitating mounting.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention deals with the field of tolerance rings and in particular bearings used with such tolerance rings positioned about the outer circumference thereof to facilitate positioning of such bearings with respect to an outer workpiece in light duty applications where some slight movement axially of the bearing within the mounting aperture of the workpiece is desirable. Normally such a workpiece would define and opening or aperture therein in which the outer race of the bearing is mountable. The present invention provides a unique means for mounting of such bearing assemblies within a workpiece utilizing a tolerance ring positionable to be captured within a groove in the outer portion of the bearing to be retained therewithin which greatly facilitates insertion of the bearing assembly into the mounted position within the aperture defined in the workpiece. Such insertion can be performed by exerting axially directed force against the outer race as is the more standard practice or can be achieved by exerting axial force against the inner race which is a unique advantage of the assembly and method of the present invention.

2. Description of the Prior Art

Numerous patents have been designed and utilized with various bearing assembly methods and configurations usually having inner and outer races rotatably movable relative to one another. Other similar configurations are also usable with the present invention as well as methods for mounting thereof. The present invention further pertains to tolerance rings for use with such bearings and as shown in U.S. Pat. No. 2,302,110 patented Nov. 17, 1942 to D. M. Dow et al and assigned to Air-Way Electric Appliance Corporation on an “Overload Release Clutch”; and U.S. Pat. No. 2,897,026 patented Jul. 28, 1959 to J. Haller et al and assigned to Halex Corporation on an “Expansion Compensating Sleeve Bearing Unit”; and U.S. Pat. No. 2,931,412 patented Apr. 5, 1960 to L. B. Wing on a “Corrugated Spring Steel Bushing”; and U.S. Pat. No. 3,061,386 patented Oct. 30, 1962 to W. Dix et al and assigned to Deutsche Star Kugelhalter, G.m.b.H. on “Tolerance Rings”; and U.S. Pat. No. 3,142,887 patented Aug. 4, 1964 to K. Hulck et al and assigned to Deutsche Star Kugelhalter G.m.b.H. on a “Method Of Making A Split Annular Tolerance Ring”; and U.S. Pat. No. 3,145,547 patented Aug. 25, 1964 to J. M. Lyons and assigned to Dana Corporation on an “Alignment Device”; and U.S. Pat. No. 3,197,243 patented Jul. 27, 1965 to A. M. Brenneke and assigned to Perfect Circle Corporation on an “Aligning And Locking Device”; and U.S. Pat. No. 3,424,287 patented Jan. 28, 1969 to A. S. Dreiding and assigned to BP Chemicals (U.K.) Limited on a “Yieldable Clutch”; and U.S. Pat. No. 3,494,676 patented Feb. 10, 1970 to J. B. S. Compton and assigned to Silentbloc Limited on “Pivotal Joint Assemblies”; and U.S. Pat. No. 3,541,810 patented Nov. 24, 1970 to G. A. Kendall and assigned to General Motors Corporation on a “Drive Transmitting Connection”; and U.S. Pat. No. 3,700,271 patented Oct. 24, 1972 to G. 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No. 4,286,894 patented Sep. 1, 1981 to RF. A. Rongley and assigned to Roller Bearing Company of America on “Tolerance Rings”; and U.S. Pat. No. 4,367,053 patented Jan. 4, 1983 to A. Stratienko et al on a “Clamping Device”; and U.S. Pat. No. 4,376,254 patented Mar. 8, 1983 to J. V. Hellmann and assigned to General Motors Corporation on an “Annular Molded Article Secured To A Shaft”; and U.S. Pat. No. 4,569,614 patented Feb. 11, 1986 to Y. Yamauchi on a “Coupling”; and U.S. Pat. No. 4,636,106 patented Jan. 13, 1987 to N. Waisbrod and assigned to Tzora Furniture Industries Ltd. on a “Coaxial Joint”; and U.S. Pat. No. 4,646,897 patented Mar. 3, 1987 to J. J. Winters and assigned to Automotive Products plc on a “Friction Clutch For A Vehicle”; and U.S. Pat. No. 4,790,683 patented Dec. 13, 1988 to A. A. Cramer, Jr. et al on a “Tolerance Ring And Shim And Method Of Use”; and U.S. Pat. No. 4,828,423 patented May 9, 1989 to A. A. Cramer, Jr. on a “Tolerance Ring And Shim”; and U.S. Pat. No. 4,898,523 patented Feb. 6, 1990 to F. L. Harwath and assigned to Suntec Industries Incorporated on a “Gear Pump With Ring-Type Shaft Retainer”; and U.S. Pat. No. 4,979,834 patented Dec. 25, 1990 to G. A. Speich and assigned to The Torrington Company on “Shafts Mounted In Bearings”; and U.S. Pat. No. 4,981,390 patented Jan. 1, 1991 to A. A. Cramer, Jr. et al and assigned to The Ray Engineering Co., Ltd. on a “Tolerance Ring With Retaining Means”; and U.S. Pat. No. 5,002,404 patented Mar. 26, 1991 to A. Zernickel et al on “Radial Rolling Bearings”; and U.S. Pat. No. 5,014,999 patented May 14, 1991 to M. Makhobey and assigned to Car-Graph, Inc. on a “Pressure Enhanced Self Aligning Seal”; and U.S. Pat. No. 5,062,721 patented Nov. 5, 1991 to M. Chiba and assigned to Nippon Seiko Kabushiki Kaisha on a “Roller Bearing With Sleeve”; and U.S. Pat. No. 5,062,761 patented Nov. 5, 1991 to C. Glachet and assigned to Euritech on a “Telescopic Manipulation Arm”; and U.S. Pat. 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Saitou and assigned to NSK Ltd. on a “Resin Composition For Resin-Banded Bearing”; and U.S. Pat. No. 5,315,465 patented May 24, 1994 to J. B. Blanks and assigned to Seagate Technology, Inc. on a “Compliant Pivot Mechanism For A Rotary Actuator”; and U.S. Pat. No. 5,336,013 patented Aug. 9, 1994 to P. E. Duffy et al and assigned to The Torrington Company on a “Separable Connecting Device For Steering Column”; and U.S. Pat. No. 5,353,566 patented Oct. 11, 1994 to A. J. Boon et al and assigned to NCR Corporation on a “Mounting Member To Eliminate Vibration And Electrostatic Discharges”; and U.S. Pat. No. 5,412,967 patented May 9, 1995 to T. Ishihara and assigned to Ishikawajima-Harima Heavy Industries Co., Ltd. on a “Method Of Making A Metallic Ring-Shaped Body”; and U.S. Pat. No. 5,421,684 patented Jun. 6, 1995 to S. T. Kluemper and assigned to General Motors Corporation on a “Vibration Damping Structure In A Bolted Assembly”; and U.S. Pat. No. 5,439,298 patented Aug. 8, 1995 to A. Zernickel et al and assigned to Ina Walzlager Schaeffler KG on a “Suspension Strut Bearing”; and U.S. Pat. No. 5,472,470 patented Dec. 5, 1995 to K. R. Kormanyos et al and assigned to Glasstech, Inc. on a “Glass Sheet Press Forming And Quenching Ring”; and U.S. Pat. No. 5,496,216 patented Mar. 5, 1996 to D. Rohrie and assigned to Valeo on a “Torsion Damper With Resilient Radial Acting Spring”; and U.S. Pat. No. 5,509,667 patented Apr. 23, 1996 to N. Klein et al and assigned to Firma Carl Freudenberg on a “Radial Lip Seal For A Shaft In A Housing”; and U.S. Pat. No. 5,524,343 patented Jun. 11, 1996 to J. B. Blanks and assigned to Seagate Technology, Inc. on a “Press-Fit Glueless Bearing Pivot Assembly”; and U.S. Pat. No. 5,539,597 patented Jul. 23, 1996 to J. B. Blanks and assigned to Seagate Technology, Inc. on a “Press-Fit Glueless Bearing Pivot Assembly For A Rotary Actuator”; and U.S. Pat. No. 5,544,330 patented Aug. 6, 1996 to D. S. Bither et al and assigned to EMC Corporation on a “Fault Tolerant Interconnect Topology Using Multiple Rings”; and U.S. Pat. No. 5,607,023 patented Mar. 4, 1997 to B. Palm and assigned to Milwaukee Electric Tool Corp. on an “Impact Absorption Mechanism For Power Tools”; and U.S. Pat. No. 5,611,416 patented Mar. 18, 1997 to A. H. Berger et al and assigned to Ford Motor Company on a “Speed Limiting Accessory Drive And Crankshaft Damper”; and U.S. Pat. No. 5,626,215 patented May 6, 1997 to A. H Berger et al and assigned to Ford Motor Company on a “Speed Limiting Accessory Drive”; and U.S. Pat. No. 5,632,562 patented May 27, 1997 to D. Kidzun et al and assigned to INA Walzlager Schaeffler KG on a “Bearing Assembly For Supporting A Shaft Without Play”; and U.S. Pat. No. 5,664,806 patented Sep. 9, 1997 to J. Vortmeyer et al and assigned to Lemforder Metallwaren AG on a “Crash System For The Steering Column In A Motor Vehicle”; and U.S. Pat. No. 5,718,131 patented Feb. 17, 1998 to J. T. Bobbitt, III and assigned to The Torrington Company on a “Steering Column Locking Assembly”; and U.S. Pat. No. 5,754,372 patented May 19, 1998 to R. G. Ramsdell et al and assigned to Quantum Corporation on an “Actuator Bearing Cartridge For Top Down Assembly”; and U.S. Pat. No. 5,794,476 patented Aug. 18, 1998 to R. A. Smietanski and assigned to Navistar International Transportation Corp. on a “Self-Aligning Flexible Gear Support For Auxiliary Gear Box”; and U.S. Pat. No. 5,819,871 patented Oct. 13, 1998 to M. Takaoka and assigned to Koyo Seiko Co., Ltd. on an “Electric Power Steering Device”; and U.S. Pat. No. 5,826,987 patented Oct. 27, 1998 to M. D. Beaman and assigned to The Torrington Company on a “Mounting Of A Shaft Within A Housing”; and U.S. Pat. No. 5,829,891 patented Nov. 3, 1998 to M. D. Beaman and assigned to The Torrington Company on a “Mounting For Steering Column”; and U.S. Pat. No. 5,839,835 patented Nov. 24, 1998 to A. Zernickel et al and assigned to Ina Walzlager Schaeffler KG on a “Self-Aligning Ball Bearing”; and U.S. Pat. No. 5,931,585 patented Aug. 3, 1999 to G. L. Malchow et al and assigned to Amana Company, L.P. on a “Bearing Mounting Structure With Reduced Dimensional Requirements”; and U.S. Pat. No. 5,937,500 patented Aug. 17, 1999 to J. T. Bobbitt, III and assigned to The Torrington Company on a “Method For Making A Steering Column Assembly”; and U.S. Pat. No. 6,062,736 patented May 16, 2000 to A. Zernickel and assigned to Ina Walzlager Schaeffler oHG on a “Pre-Tensioned Radial Rolling Bearing”; and U.S. Pat. No. 6,163,441 patented Dec. 19, 2000 to R. L. Wood et al and assigned to Seagate Technology LLC on a “Resonance Dampening Actuator Bearing Assembly”; and U.S. Pat. No. 6,179,473 patented Jan. 30, 2001 to F. Ponson et al and assigned to SKF France on a “Roller Bearing Of Steering Column For Motor Vehicles”; and United States Publication No. U.S. 2001/0002630 A1 published Jun. 7, 2001 to A. Watanabe et al on an “Electric Steering Apparatus”; and U.S. Pat. No. 6,261,061 patented Jul. 17, 2001 to E. E. Pfaffenberger and assigned to Rolls-Royce Corporation on a “Method And Apparatus For Mounting A Bearing”; and U.S. Pat. No. 6,269,709 patented Aug. 7, 2001 to H. C. Sangret and assigned to TRW Inc. on an “Apparatus For Automatic Control Of The Clearance Between Gears”; and U.S. Pat. No. 6,288,878 patented Sep. 11, 2001 to N. F. Misso et al and assigned to Seagate Technology LLC on a “Tolerance Ring With High Hoop Strength To Resist Deformation”; and U.S. Pat. No. 6,288,879 patented Sep. 11, 2001 to N. F. Misso et al and assigned Seagate Technology LLC on a “Top Down Assembly Of A Disk Drive Actuator Using A Tolerance Ring And A Post”; and U.S. Pat. No. 6,318,900 patented Nov. 20, 2001 to J. D. Bere et al and assigned to Siemens Automotive Inc. on a “Ball Bearing Mounting Member”; and U.S. Pat. No. 6,318,232 patented Nov. 20, 2001 to N. Lemke et al and assigned to Mercedes Benz Lenkungen GmbH on a “Pressure-Cutoff Arrangement For An Auxiliary Power Steering System In The End Positions Of The Steering Lock”; and U.S. Pat. No. 6,333,839 patented Dec. 25, 2001 to N. F. Misso et al and assigned to Seagate Technology LLC on a “Tolerance Ring With Low Consistent Installation Force Profile”; and U.S. Pat. No. 6,347,462 patented Feb. 19, 2002 to K. M. Steinich and assigned to ASM Automation Sensorik Messtechnik GmbH on a “Measuring Cable Travel Sensor With Housing”; and U.S. Pat. No. 6,348,000 patented Feb. 19, 2002 to r. D. Cooke et al and assigned to AP Time Limited on “Torsional Vibration Dampers”; and U.S. Pat. No. 6,375,360 patented Apr. 23, 2002 to U. Weisskopf et al and assigned to INA on a “Ball Bearing”; and U.S. Pat. No. 6,375,574 patented Apr. 23, 2002 to A. J. Young et al and assigned to AP TMF Limited on “Torsional Vibration Dampers”; and U.S. Pat. No. 6,378,678 patented Apr. 30, 2002 to B. Armitage et al and assigned to Automotive Products UK, LTD on “Twin Mass Flywheel Assemblies”; and U.S. Pat. No. 6,411,472 patented Jun. 25, 2002 to D. S. Allsup and assigned to Seagate Technology LLC on a “Dual Metal Laminate Tolerance Ring For Acoustic And Vibration Damping”; and U.S. Pat. No. 6,416,229 patented Jul. 9, 2002 to M. Wolf and assigned to INAS Walzlager Schaeffler oHG on a “Ball Bearing”; and U.S. Pat. No. 6,424,066 patented Jul. 23, 2002 to A. L. Watson et al and assigned to Camco International, Inc. on a “System For Reducing Wear And Improving Longevity Of A Electric Submergible Pumping System”; and U.S. Pat. No. 6,430,836 patented Aug. 13, 2002 to K. M. Steinich and assigned to ASM Automation Sensorik Messtechnic GmbH on a “Pull Element Travel Sensor”; and U.S. Pat. No. 6,448,679 patented Sep. 10, 2002 to J. Imlach on a “Passive Magnetic Support And Damping System”; and U.S. Design Pat. No. D380,959 patented Jul. 15, 1997 to C. A. Mitchell and assigned to The Torrington Company on a “Tolerance Ring”.

SUMMARY OF THE INVENTION

The method of the present invention mounts or attaches a light duty bearing having a circumferential groove defined peripherally therearound into a workpiece aperture with a metallic tolerance ring retained within the groove. This tolerance ring retains the bearing in a frictionally resisted movable manner with respect to the workpiece aperture. The method usually includes providing a bearing with an inner race member which is rotatably mounted in an outer race member and includes an arcuate convex outer surface thereon. This outer arcuate convex surface is preferably of a generally cylindrical shape and will define a groove extending circumferentially therearound which is generally circular in shape.

A tolerance ring provided of a flexibly resilient metallic material which includes a main band section which is preferably ring-shaped. The tolerance ring preferably includes a plurality of wave sections extending radially outwardly therefrom. The tolerance ring also is preferably split laterally to define first and second longitudinal ends thereon. The main band section of the tolerance ring is preferably of a thickness which is less than the depth of the circumferential groove in order to facilitate retaining of the main band section completely within the circumferential groove whenever the tolerance ring is positioned therein.

In accordance with the method of the present invention, force is exerted on the tolerance ring to urge the first and second longitudinal ends apart to further open up the ring-shaped main band section. In this manner the tolerance ring can be moved to a position extending around and over the outer surface of the bearing and into the circumferential groove thereof with the wave protrusions extending radially outwardly from the groove. Normally the tolerance ring is simply expanded manually or automatically such as by machine and is then is positioned about the outer portion of the bearing in order to be allowed to snap into the groove which is defined between first and second circular rims which extend about the outer surface of the outer race of the bearing in order to define the groove therebetween. Since the tolerance ring is of a flexibly resilient metallic material, when placed in the groove and released it will return to the steady state configuration thereof in a position completely retained within the groove with only the wave protrusions extending outwardly therefrom radially.

The releasing of the force on the tolerance ring allows the first and second longitudinal ends thereof to resiliently move toward one another and thereby facilitates movement of the main band section to return to the steady state flexibly resilient configuration with the first and second longitudinal ends positioned adjacent to one another wherein the ring-shaped main band section is positioned within the groove. In this manner the main band section will be retained within the groove and the wave protrusions will extend radially outwardly therefrom. It is preferable that the wave protrusions be defined approximately perpendicular to the arcuate outer surface of the bearing. Also, preferably the wave protrusions are regularly positioned around the ring-shaped main band section thereof in order to maintain concentricity of the bearing with respect to the workpiece aperture.

Once the tolerance ring is positioned within the groove, the bearing will be urged or forced into the aperture of the workpiece manually or by mechanical automated means such as by pressing thereof. It is an important advantage of the present invention that the force for insertion of the bearing can be placed on either the outer race member of the bearing or on the inner race member thereof. The possibility of exerting the inserting pressing force against the inner race is an important advancement of the present invention. Normally such an process for bearing insertion is impossible due to the deforming of the balls or other rollers positioned between the inner and outer race of the bearings. Thus heretofore bearing insertion was performed by exerting the force on the outer race only. However, with the light duty movable mounting desired by the light duty bearing application of the present invention the pressing force can be exerted against either the inner or the outer race. The movable mounting of the assembly of the present invention is preferably frictionally resisted by the radially outward force of the waves of the tolerance rings directed against the interior wall of the workpiece aperture. Thus with those light duty applications for which is present assembly is useful, a frictionally resisted movable engagement between the workpiece and the bearing is desired such as for light duty equipment like vacuum cleaners.

When properly positioned within the workpiece aperture the outer arcuate surface of the bearing will abut the workpiece aperture with the tolerance ring positioned in the groove located therebetween. In this manner the tolerance ring will exert bias therebetween to facilitate securement therebetween. The level of securement achieved can vary widely. It can comprise severely restricted movable securement which limits any significant relative movement between the bearing and the aperture of the workpiece. Alternatively the engagement therebetween can be a frictionally restricted movable mounting which allows much relative movement of the outer surface of the bearing relative to the aperture of the workpiece. This type of mounting is often called a low-duty mounting since controlled limited frictionally engaged relative movement between the bearing and the mounting aperture of the workpiece is desirable.

In the preferred configuration the main band section of the tolerance ring is provided with a thickness such that it is less than the depth of the circumferential groove defined in the arcuate convex outer surface to facilitate retaining of the main band section completely within the circumferential groove responsive when the bearing is mounted within a workpiece. It is desirable to position the tolerance ring completely within the groove however sometimes it is necessary to compensate for slight dimensional variations in the size and shape of the tolerance ring or the surfaces to which it abuts in order to assure retainment thereof completely within the groove itself. As such, it is advantageous to provide the main band section of the tolerance ring with a thickness of between 0.005 inches and 0.010 inches less than the depth of the circumferential groove defined in the arcuate convex outer surface in order to be assured that the main band section thereof is completely retained within the groove regardless of slight variations in the dimensions or shape of the tolerance ring itself or of the surfaces against which it abuts.

When the main band section is positioned in the groove the two longitudinal ends of this tolerance ring can be positioned immediately adjacent to one another but spaced apart or, after placement in the groove, can be positioned in abutment with respect to one another. Either configuration will function properly in accordance with the method and product of the present invention.

The configuration of the bearing assembly of the present invention will include a bearing means with an outer body member having an arcuate convex outer surface which defines the groove therein. The outer body member of the bearing is movably mountable with respect to the aperture of the workpiece but this movement can be severely restricted by the frictional engagement therebetween caused by the tolerance ring held therebetween.

The tolerance ring is preferably formed of a main band means which is ring-shaped and is split laterally therealong. This lateral split defines a first end and a second end on the main band. These ends allow the flexibly resilient tolerance ring to be opened somewhat by separating of the ends to facilitate movement over the outer rims of the bearing outer arcuate surface to allow placement thereof into the groove. The tolerance ring also includes a plurality of protruding wave means which extend radially outwardly therefrom to facilitate engagement between the grooved surface of the outer bearing race and the surface of the workpiece inside of the aperture thereof.

It is an object of the present invention to provide a bearing assembly and method of insertion thereof into the aperture of a workpiece wherein the forces of insertion can be applied on the inner race member of the bearing.

It is an object of the present invention to provide a bearing assembly and method of insertion thereof into the aperture of a workpiece wherein the forces of insertion can be applied on the outer race member of the bearing.

It is an object of the present invention to provide a bearing assembly and method of insertion thereof into the aperture of a workpiece including a tolerance ring retained within a groove on the exterior surface of the bearing which can be easily assembled.

It is an object of the present invention to provide a bearing assembly and method of insertion thereof into the aperture of a workpiece including a tolerance ring retained within a groove on the exterior surface of the bearing which allows placement into the workpiece in a fast and efficient manner or operation due to the fact that the tolerance ring is captured within the groove.

It is an object of the present invention to provide a bearing assembly and method of insertion thereof into the aperture of a workpiece including a tolerance ring retained within a groove on the exterior surface of the bearing which can be made with a tolerance ring of flexibly resilient spring steel material.

It is an object of the present invention to provide a bearing assembly and method of insertion thereof which can be made with many different configurations of protruding waves extending radially outwardly from the tolerance ring of the bearing assembly to facilitate engagement with the workpiece aperture.

It is an object of the present invention to provide a bearing assembly and method of insertion thereof into the aperture of a workpiece including a tolerance ring retained within a groove on the exterior surface of the bearing which should include a plurality of regularly spaced protruding waves extending radially outward from the main band to maintain concentricity between the bearing and the workpiece aperture.

It is an object of the present invention to provide a bearing assembly and method of insertion thereof into the aperture of a workpiece including a tolerance ring retained within a groove on the exterior surface of the bearing which is easily maintained.

It is an object of the present invention to provide a bearing assembly and method of insertion thereof into the aperture of a workpiece including a tolerance ring retained within a groove on the exterior surface of the bearing which is relatively inexpensive for light-duty usage.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

The present invention provides a bearing assembly10which is adapted to be placed into an aperture14defined in a workpiece12to provide low frictional rotational capability with respect thereto or fixed securement therebetween. Such a bearing assembly10normally includes an outer bearing race38which is mounted within the aperture14of workpiece12to minimize or restrict relative rotation therebetween. An inner bearing race40is mounted in such a manner as to be rotatably movable at a position within the outer bearing race38. In this manner a workpiece mounted within the inner bearing race40will be capable of rotational freedom relative to the workpiece12. This configuration is conventional bearing technology.

The present invention, however, includes a unique configuration for a light duty bearing assembly10which is mountable through a unique method to movably mount the bearing with respect to the workpiece aperture14utilizing a metallic tolerance ring22which has a main band section which is preferably ring-shaped. This mounting allows restricted relative movement between the bearing and the workpiece aperture which is resisted by frictional forces of the tolerance ring22positioned therebetween. Tolerance ring22is preferably positionable within a groove16which is preferably circular in shape and extends circumferentially about the outer body member18of the bearing10. This groove16defined in the outer body member18is for the purpose of receiving the metallic ring-shaped tolerance ring22therein. This tolerance ring has the capability of selectively affixing the bearing assembly10with respect to the workpiece12and, in particular, the aperture14thereof.

One of the primary aspects of the present invention is in the unique method of mounting the bearing into the workpiece aperture with the metallic tolerance ring positioned about the exterior thereof. The inclusion of a circumferential groove in the outer bearing surface allows a uniquely advantageous method of insertion and can be used for many different types of bearing applications and greatly simplifies proper mounting of the bearing in the working location thereof within the aperture14of the workpiece12.

Preferably the bearing assembly10includes an arcuate convex outer surface20which surface defines the groove16extending circumferentially therearound. In the preferred configuration the arcuate convex outer surface20is cylindrically shaped and includes a first rim means42extending therearound and a second rim means44extending therearound positioned spatially distant from the first rim means. In this manner the first rim means42and the second rim means44can define therebetween the groove means16which is preferably circular and extend circumferentially about the arcuate convex outer surface20.

When so configured the bearing of the bearing assembly10will define this circumferential groove16which is adapted to receive the metallic ring-shaped tolerance ring22therewithin. This tolerance ring22preferably is ring-shaped with a lateral split25located extending laterally completely through the ring22. The tolerance ring22includes a main band section24which terminates at a first end26and oppositely terminates at a second end28. First end26and second end28define therebetween the lateral split25.

The tolerance ring22also includes a plurality of waves30which protrude outwardly from the groove16when the main band24of tolerance ring22is positioned therewithin. These protruding waves30preferably extend outwardly in a radial direction32as shown best inFIG. 4. The thickness34of the main band24is preferably less than the depth36of the groove16such that the main band section24of the tolerance ring22can be contained completely within the groove16when the bearing assembly10is mounted within the workpiece aperture14. With this configuration the waves30will protrude radially outwardly in the direction shown by arrow32toward the body of the workpiece12and exert a bias or force against the inside of the workpiece aperture14which will maintain the bearing assembly10mounted within the workpiece aperture14. Preferably this position will place the outer bearing race38and the inner bearing race40concentric with respect to the workpiece aperture14. This “concentricity” is an important aspect of the present invention in maintaining the proper alignment of rotating parts relative to one another and it is created by the regular spacing of a plurality of protruding waves30extending radially outwardly from the main band24of the tolerance ring22in the radial direction32to exert force against the workpiece aperture14evenly therearound.

In the preferred configuration the main band24will have a main band thickness34which is significantly less than the depth36of groove16. Preferably the depth36of the groove16will be 0.005 inches to 0.010 inches greater than the main band thickness34. This size difference is important to compensate for variations in the size and shape of the tolerance ring22as well as the arcuate convex outer surface20of the bearing11and to possibly compensate for variations in the shape of the workpiece aperture14.

When practicing the method of the present invention as schematically illustrated inFIG. 4, initially the tolerance ring22is placed in the steady state position as shown in step A ofFIG. 4. This figure shows the tolerance ring22in the steady state relaxed position with the first end26and second end28thereof adjacent to one another but somewhat spaced apart. It must be appreciated that the material from which the tolerance ring22is formed is a flexibly resilient material such as spring steel. This flexibly resilient material is important for the purpose of providing flexibly resilient force by the protruding waves30upon the interior of the workpiece aperture14. This flexible resilience is also important for allowing the first and second ends26and28to flex outwardly away from one another to facilitate mounting of the tolerance ring within the circular groove16.

FIG. 4, step B, shows the first step in the method of affixing the bearing in place wherein force is exerted along force arrows46and/or48. Force exerted along directions46is directed on the adjacent portions of the main band24in such a manner as to further expand the central opening of the ring-shaped tolerance ring22and in this manner separate the first and second ends26and28from one another significantly. This relationship is shown best in step B ofFIG. 4. Another way of expanding the central opening of the tolerance ring22can be achieved by exerting force in the direction shown by end force arrows48. The exertion of force in the direction shown by arrows48will also significantly increase the size of the opening within the ring-shaped tolerance ring22. Once the tolerance ring is forced into the more opened position it can be moved into the groove as schematically illustrated in step C ofFIG. 4. That figure shows the bearing11ready to receive the tolerance ring22for placement into the circular circumferential groove16extending therearound.

Once the tolerance ring22is in position within the groove the force exerted through arrows46and/or48can be released which allows the flexibly resilient tolerance ring22to return to the steady state position as shown in section A ofFIG. 4in position within the circular groove16. This assembly can then be inserted as shown in section D ofFIG. 4into the aperture14of workpiece12such that the bearing assembly10can be secured with respect to the workpiece12and in particular such that the arcuate convex outer surface20of bearing assembly10can be firmly retained by the workpiece aperture14. The force of insertion can be provided by a conventional press or other force exerting device. This force can be exerted against the outer bearing race38in the conventional manner or can be exerted against the inner bearing race40which is an important advantage of the present invention. Normally exerting force against the inner bearing race40is not possible since it will seriously deform the balls or rollers located between the inner bearing race40and the outer bearing race38which is responsible for allowing relative rotational movement therebetween. However, with the unique method of the present invention which is useful for light duty bearing applications, such force used to press the bearing11in place within the workpiece aperture14can be applied on the inner bearing race40which is much more convenient and easier to maintain concentricity during mounting thereof.

The mounting of the bearing assembly10with respect to the workpiece12in the workpiece aperture14can allow only highly restricted relative movement such that little movement occurs between the arcuate convex outer surface20of the bearing assembly10and the workpiece12. With such restricted movable connections often it is best to have the bearing assembly10pressed into place utilizing a hydraulic or other similarly powered pressing apparatus. However the present invention has been found to be well adapted to use with light-duty applications wherein some movement is desirable between the bearing assembly10and the workpiece12. This relative movement will be severely limited and will be restricted by a the frictional engagement between the workpiece aperture14and the protruding waves30of the tolerance ring22. Thus the tolerance ring22can be configured in such a manner that movable mounting of the bearing assembly10within the workpiece12is possible or a slightly more movable interconnection is also achievable wherein the movement is still somewhat frictionally resisted or restricted thereby requiring some level of force to cause relative movement between the bearing assembly10and the workpiece12. The application where some movement is possible is often referred to as light-duty or limited duty bearing mounting application and is commonly utilized in small appliances such as vacuum cleaners and the like.

As such, the steps of the method of the present invention are set forth inFIG. 4, steps A, B, C and D. It is clearly important to appreciate that the tolerance ring of the present invention must be split in order to practice this method since expansion or opening of the tolerance ring22is necessary in order to position it within the groove16of the workpiece12.

An important consideration of the present invention is that the tolerance ring is “self-securing” during assembly. That is, the positioning of the tolerance ring within the circumferential groove16defined in the outer body member18of bearing11is an important advantage especially during such assembly because the tolerance ring22will automatically be maintained in the proper position on the arcuate convex outer surface20of the bearing11at all times during insertion. Often during insertion with conventional tolerance rings positioned about the external surface of conventional bearings it is difficult to maintain the tolerance ring in the correct position extending peripherally around the bearing. With the defining of the groove16between the first and second rims42and44of the outer body member18in the bearing assembly10of the present invention, the correct relationship between the positioning of the tolerance ring22and the bearing11will be maintained proper at all times during mounting of the bearing within the workpiece aperture14. Thus the speed of automated assembly of such bearings into workpieces12on an assembly line is significantly expedited.

The configuration of the bearing11itself in the present invention can be of any conventional bearing configuration. A conventional bearing is shown in the Figures illustrating the outer bearing race38, the inner bearing race40and the ball means50positioned therebetween. This present invention is usable with an inner and outer race rotatable with respect to one another through any conventional bearing design available as of the current time or that might be developed in the future such as ball bearings, pin bearings, roller bearings, friction bearings or any other conceivable bearing interconnection means which would allow an inner and outer race to rotate with respect to one another generically. As such, the unique advantage of the present invention is in the method of assembly and the defining of a groove16in the arcuate convex outer surface20of a generic bearing11and the relative sizing and positioning of the bearing with respect to the workpiece aperture14and the tolerance ring22which applied directly to light duty uses.

It is important to consider that the present invention is particularly applicable to such light-duty or light force tolerance ring installations. In those installations where frictional movement of the bearing11with respect to the workpiece12is acceptable or even desired, it is often difficult to maintain the tolerance ring in a proper position during mounting since the forces exerted on the tolerance ring22and exerted by the tolerance ring22are minimal in order to allow the frictional movement of the light-duty bearing mounting system. The present invention overcomes the difficulty of retaining the tolerance ring in proper position even after placement within the workpiece aperture14by the unique method of the present invention wherein the arcuate outer surface of the bearing includes a groove for holding the tolerance ring and the tolerance ring includes a main band section which is capable of being completely captured within that groove. This alignment can also be better maintained since the present invention is designed for mounting of the bearing11within the workpiece aperture14by allowing the exerting of the pressing forces required for insertion against the inner bearing race40axially.

While particular embodiments of this invention have been shown in the drawings and described above, it will be apparent, that many changes may be made in the form, arrangement and positioning of the various elements of the combination. In consideration thereof it should be understood that preferred embodiments of this invention disclosed herein are intended to be illustrative only and not intended to limit the scope of the invention.