US20070124935A1

US20070124935A1 - Methods and apparatus for installing a bearing

Info

Publication number: US20070124935A1
Application number: US11/295,054
Authority: US
Inventors: James Crowell; James Holich; Robert Schiffli; Samir Joshi
Original assignee: General Electric Co
Current assignee: General Electric Co
Priority date: 2005-12-06
Filing date: 2005-12-06
Publication date: 2007-06-07

Abstract

A method for installing a bearing into a component using an insert includes aligning the insert with an opening within the component that has a dimension that is less than a complimentary dimension of the insert, aligning the bearing with the insert, inserting the insert at least partially into the opening such that at least a portion of a surface defining the opening is deformed by the insert, and inserting the bearing into the opening after the insert such that the bearing is positioned at least partially with the opening and is at least partially retained within the opening by a portion of the surface defining the opening.

Description

BACKGROUND OF THE INVENTION

The methods and apparatus described herein relate generally to bearings, and more specifically to installing bearings into a component, such as, but not limited to, an endshield for an electric motor or generator.
Bearings are sometimes installed in components to facilitate relative movement (e.g., rotational movement) between the component and another component. However, clearance between an outer periphery of the bearing and the component the bearing is installed in may allow movement between therebetween. Such movement of the bearing with respect to the component may generate or increase noise during operation thereof and/or may generate or increase vibration of the bearing with respect to the component. Such noise may be undesirable during operation of the component and/or operation of a machine or assembly including the component and the bearing. For example, bearing noise from residential heating, ventilation, and air-conditioning (HVAC) equipment may be a nuisance to residents. Moreover, such movement may facilitate increasing wear of the bearing and/or the component due to contact therebetween, possibly increasing a failure rate of the bearing, the component, and/or a machine or assembly including the component and the bearing.
For example, endshields for electric motors sometimes include a rotary bearing for interconnecting a rotor shaft of the motor with the endshield and facilitating relative movement therebetween. In some known endshields, the rotary bearing is positioned within a bearing pocket of the endshield such that there is a clearance (sometimes referred to as a “slip fit”) between at least portion of an outer periphery of the bearing, for example an outer race of the bearing, and at least a portion of an inner surface of the bearing pocket. The clearance of the lip fit of the bearing may facilitate increasing noise, vibration, wear, and/or failure of the bearing, the bearing pocket, and/or the motor generally. Irregularities of an outer surface of the outer race of the bearing and/or the inner surface of the bearing pocket, for example a roughness, a variation in radius, and/or an incorrect dimension, may further facilitate such relative movement between the bearing and the bearing pocket, thereby possibly further increasing noise, vibration, wear, and/or failure of the bearing, the bearing pocket, and/or the motor generally. Similarly, particles extending outwardly from, and/or wear particles broken away from, the outer race of the bearing and/or the inner surface of the bearing pocket acting as, for example, an abrasive, may further accelerate noise, vibration, wear, and/or failure. For example, wear particles from endshields that are fabricated from aluminum sometimes include oxidized aluminum, similar to the known industrial abrasive aluminum oxide. Moreover, over time relative movement between the bearing and the bearing pocket may enlarge the bearing pocket, sometimes referred to as “pound-out”, thereby possibly further accelerating noise, vibration, wear, and/or failure of the bearing, the bearing pocket, and/or the motor generally. Pound-out may sometimes be exacerbated if the bearing and bearing pocket are formed from different materials. For example, different thermal expansion rates of the different materials may further increase clearance between the bearing and the bearing pocket at operational temperatures of the motor.
To reduce or eliminate relative movement between a bearing and a component, the bearing may be fixedly secured to the component using a clamp and/or other means. However, such clamps and/or other means may increase a cost and/or complexity of the bearing/component assembly. Moreover, some known bearings are press-fit into the bearing pocket to facilitate reducing or preventing relative movement between the bearing and the bearing pocket. However, press-fitting the bearing into the bearing pocket may deform and/or damage the outer race of the bearing. As discussed above, such damage and/or deformation may facilitate generating or increasing noise, vibration, wear, and/or failure of the bearing, the bearing pocket, and/or the motor generally. Moreover, the dimensions and tolerances of the bearing pocket and/or the bearing may be need to be considered to ensure a predetermined fit between the bearing and bearing pocket, possibly increasing a difficulty and/or cost of fabricating the bearing/component assembly. For example, if the bearing pocket is not sufficiently round, press-fitting the bearing may result in deformation and/or damage to the bearing outer race.

BRIEF DESCRIPTION OF THE INVENTION

In one aspect, a method is provided for installing a bearing into a component using an insert. The method includes aligning the insert with an opening within the component that has a dimension that is less than a complimentary dimension of the insert, aligning the bearing with the insert, inserting the insert at least partially into the opening such that at least a portion of a surface defining the opening is deformed by the insert, and inserting the bearing into the opening after the insert such that the bearing is positioned at least partially with the opening and is at least partially retained within the opening by a portion of the surface defining the opening.
In another aspect, apparatus for installing a bearing includes a component including an opening therein having two opposite open ends. The opening is configured to at least partially receive the bearing. The apparatus also includes an insert configured to be received within the opening. The insert has a dimension that is greater than a complimentary dimension of the opening for deforming at least a portion of a surface defining the opening when received within the opening. The bearing is configured to be received within the opening and retained within the opening by at least a portion of the surface defining the opening after the insert has been at least partially received within the opening.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of an exemplary endshield and bearing assembly for an electromagnetic device.
FIG. 2 is another perspective view of the exemplary endshield and bearing assembly shown in FIG. 1.
FIG. 3 is a cross-sectional schematic view of the exemplary bearing shown in FIGS. 1 and 2, the exemplary endshield shown in FIGS. 1 and 2, and an exemplary embodiment of an insert for installing the bearing into the endshield.
FIG. 4 is a perspective view of the exemplary insert shown in FIG. 3.
FIG. 5 is cross-section of the exemplary insert shown in FIGS. 3 and 4 taken along line 5-5 of FIG. 4.
FIG. 6 is flow chart illustrating an exemplary embodiment of a method for installing the exemplary bearing shown in FIGS. 1-3 into the exemplary endshield shown in FIGS. 1-3.
FIG. 7 is a cross-sectional schematic view illustrating an installation step of the method shown in FIG. 6.
FIG. 8 is a cross-sectional schematic view illustrating another installation step of the method shown in FIG. 6.
FIG. 9 is a cross-sectional schematic view illustrating the exemplary bearing shown in FIGS. 1-3, 7, and 8 installed in the exemplary endshield shown in FIGS. 1-3, 7, and 8.
Corresponding reference characters indicate corresponding parts throughout the several views of the drawings.

DETAILED DESCRIPTION OF THE INVENTION

Referring now to the drawings, and more specifically to FIGS. 1 and 2, an exemplary embodiment of an endshield and bearing assembly for an electromagnetic device (not shown) is designated in its entirety by the reference numeral 10. Assembly 10 includes an endshield (generally designated by 12 and only a portion of which is shown) and a bearing (generally designated by 14). Endshield 12 includes a body 16 having an opening (generally designated by 18), sometimes referred to as a “bearing pocket”, for receiving bearing 14.
Opening 18 may include any size and/or shape for receiving any size, shape, and/or type of bearing, such as, but not limited to, ball bearings, roller bearings, ball thrust bearings, roller thrust bearings, tapered roller bearings, magnetic bearings, miniature bearings, instrument bearings, precision bearings, small bearings, medium bearings, large bearings, light bearings, heavy bearings, extra-heavy bearings, rotary bearings, linear bearings, and/or bearings facilitating other directions of relative movement between two components. However, in the exemplary embodiment, opening 18 is sized and shaped for receiving the exemplary bearing 14 therein. For example, as shown in FIGS. 1 and 2, in the exemplary embodiment opening 18 is generally cylindrical shaped. Moreover, and for example, as shown in FIGS. 3, 7, 8, and 9 in the exemplary embodiment opening 18 extends between two opposite ends (generally designated by 20 and 22). In the exemplary embodiment, each of ends 20 and 22 is generally open. Opening 18 includes an inner diameter 24 defined by an inner surface 26 thereof. Although as discussed above opening 18 may include any size, in some embodiments diameter 24 of opening 18 is between about 1 inch and 10 inches. As described in more detail below, in some embodiments, a finished size and shape of endshield opening 18 is formed by installation of bearing 14 into endshield 12. In some embodiments, endshield 12 is an endshield for an electric motor. In some embodiments, endshield 12 is an endshield for an electric generator. Endshield 12 may be fabricated using any suitable process and/or means, and may be fabricated from any material. For example, in some embodiments endshield 12 is stamped from a sheet of material or cast. Moreover, and for example, in some embodiments endshield 12 is fabricated from steel or aluminum.
Bearing 14 may include any size, shape, and/or may be any type of bearing, such as, but not limited to, ball bearings, roller bearings, ball thrust bearings, roller thrust bearings, tapered roller bearings, magnetic bearings, miniature bearings, instrument bearings, precision bearings, small bearings, medium bearings, large bearings, light bearings, heavy bearings, extra-heavy bearings, rotary bearings, linear bearings, and/or bearings facilitating other directions of relative movement between two components. In the exemplary embodiment, bearing 14 is a rotary bearing that facilitates relative rotational movement between endshield 12 and a rotor shaft (not shown) of the electromagnetic device. Moreover, in the exemplary embodiment, bearing 14 includes a generally cylindrical outer surface 28, which defines an outer diameter 30 thereof. Outer diameter 30 of bearing 14 is greater than inner diameter 24 of opening 18. Although outer diameter 30 of bearing 14 may be greater than inner diameter 24 of opening 18 by any value, in some embodiments outer diameter 30 is between about 0.0001 inches and 0.010 inches greater than inner diameter 24. As can be appreciated from the description of bearing 14 and opening 18 herein, as well as FIGS. 1, 2, 3, 7, 8, and 9, the size and shape of outer surface 28 of bearing 14 and inner surface 26 of opening 18, whether different, are generally complimentary to facilitate reception of bearing 14 within opening 18. For example, diameter 24 of opening 18 and diameter 30 of bearing 14, although different, are generally complimentary. Although as discussed above bearing 14 may include any size, in some embodiments diameter 30 of bearing 14 is between about 1 inch and 10 inches.
FIG. 3 is a cross-sectional view of endshield 12, bearing 14, and an insert (generally designated by 100) for installing bearing 14 into endshield 12, and more specifically opening 18. Insert 100 may include any size and/or shape to be received within, and at least partially deform, any size and/or shape opening. However, in the exemplary embodiment, insert 100 is sized and shaped to be received within, and at least partially deform, opening 18. For example, in the exemplary embodiment, and as shown in FIGS. 4 and 5, insert 100 includes a generally circular cross-sectional shape. Referring again to FIG. 3, insert 100 includes an outer diameter 102 defined by an outer surface 104 thereof. As can be appreciated from the description of insert 100 and opening 18 herein, as well as FIGS. 3 and 7, the size and shape of outer surface 104 of insert 100 and inner surface 26 of opening 18, whether different, are generally complimentary to facilitate reception of insert 100 within opening 18. For example, diameter 24 of opening 18 and diameter 102 of insert 100, although different, are generally complimentary. Although outer diameter 102 is shown in the exemplary embodiment as being adjacent an end (generally designated by 106) of insert 100, outer diameter 102 may be located anywhere on insert 100. Moreover, although as discussed above insert 100 may have any shape (including a generally uniform diameter), in the exemplary embodiment the diameter of insert 100 is generally variable along a length 108 thereof. In some embodiments, insert 100 includes a generally conical shape. As shown in FIG. 4, in the exemplary embodiment, insert 100 includes a generally frustoconical shape. Although as discussed above insert 100 may include any size, in some embodiments outer diameter 102 of insert 100 is between about 1 inch and 10 inches.
Outer diameter 102 of insert 100 is greater than inner diameter 24 of opening 18 such that insert 100 deforms at least a portion of opening 18 when insert 100 is received therein. More specifically, and as shown in FIG. 7, as insert 100 is inserted into opening 18 the greater diameter 102 of insert 100 than inner diameter 24 of opening 18 deforms inner surface 26 of opening 18. As will be described below, when bearing 14 is inserted into opening 18 after insert 100, bearing 14 is securely retained within opening 18 via elastic deformation caused by insert 100 and the resulting “interference” between inner surface 26 of opening 18 and outer surface 28 of bearing 14. In some embodiments, in addition to elastic deformation, insert 100 plastically deforms at least a portion of inner surface 26 of opening 18. Although outer diameter 102 of insert 100 may be greater than inner diameter 24 of opening 18 by any value, in some embodiments outer diameter 102 is between about 0.0001 inches and 0.010 inches greater than inner diameter 24. Accordingly, and although insert 100 may deform inner surface 26 by any value and in any direction, in some embodiments insert 100 deforms inner surface 26 between about 0.0001 inches and 0.010 inches generally radially away from a central longitudinal axis 108 of opening 18. A relationship between outer diameter 102 of insert 100 and inner diameter 24 of opening 24, and in some embodiments an elasticity, for example due to a strength, a thickness and/or a material, of endshield 12 adjacent inner surface 26, may be selected to provide a pre-determined amount of elastic deformation of endshield 12. Similarly, a relationship between outer diameter 102 of insert 100 and outer diameter 30 of bearing 14 can be selected to provide a pre-determined amount of interference between surfaces 26 and 28 resulting from the elastic deformation of endshield 12. In some embodiments, outer diameter 102 of insert 100 is substantially equal to outer diameter 30 of bearing 14. However, in some embodiments, outer diameter 102 of insert 100 is greater than outer diameter 30 of bearing 14. For example, a relationship between outer diameter 102 of insert 100 and inner diameter 24 of opening 24, and in some embodiments an elasticity, for example due to a strength, a thickness, and/or a material, of endshield 12 adjacent inner surface 26, may be selected to provide a pre-determined amount of plastic deformation of endshield 12. When insert 100 plastically deforms endshield 12 and insert outer diameter 102 is greater than bearing outer diameter 30, the plastic deformation of endshield 12 may reduce a variation in tangential stresses, possibly resulting in a reduction in the variation of interference between surfaces 26 and 28.
FIG. 6 is flow chart illustrating an exemplary embodiment of a method (generally designated by 200) for installing bearing 14 (FIGS. 1-3, 7, 8, and 9) into endshield 12 (FIGS. 1-3, 7, 8, and 9). Method 200 includes aligning 202 insert 100 with opening 18, and aligning 204 bearing 14 with insert 100. In some embodiments, and as shown in FIG. 7, aligning 202 insert 100 with opening 18 includes concentrically aligning insert 100 with opening 18 by aligning insert 100 with central longitudinal axis 108, and aligning 204 bearing 14 with insert 100 includes concentrically aligning bearing 14 with insert 100 by aligning bearing 14 with central longitudinal axis 108. Referring again to FIG. 6, once aligned 202, 204, insert 100 and bearing 14 are inserted 206 into opening 18, for example, by pressing on bearing 14. For example, as shown in FIG. 7, insert 100 and bearing 14 are inserted 206 into end 20 of opening 18. Although insert 100 and bearing 14 may be inserted into opening 18 using any suitable method and/or using any suitable means, in some embodiments insert 100 and bearing 14 are pressed into opening 18 using an arbor press or a hydraulic press. Moreover, and for example, in the exemplary embodiment insert 100 and bearing 14 are inserted into opening 18 using a driver (generally designated by 300). In the exemplary embodiment, driver 300 includes a member 302 for applying force to bearing 14, and a member 304 for applying force to insert 100.
As insert 100 moves through opening 18, outer diameter 102 of insert 100 deforms inner surface 26 of opening 18. For example, outer diameter 102 generally deforms inner surface 26 such that inner surface 26 moves generally radially away from central longitudinal axis 108. As discussed above, although insert 100 may deform inner surface 26 by any value, in some embodiments insert 100 deforms inner surface 26 between about 0.0001 inches and 0.010 inches generally radially away from central longitudinal axis 108 of opening 18. Insert 100 and bearing 14 are inserted 206 into opening 18 until bearing 14 is in a predetermined position within opening 18 along axis 108. In some embodiments, insert 100 is removed 208 from opening 18 once bearing 14 is in the predetermined position. Insert 100 can be removed 208 from opening 18 in any suitable manner and/or using any suitable means, however, in the exemplary embodiment insert 100 is removed from end 22 of opening 18 using member 304 of driver 300, as shown in FIG. 8.
Bearing 14 is retained within opening 18 by interference between opening inner surface 26 and bearing outer surface 28 caused by elastic deformation of opening inner surface 26. More specifically, as shown in FIG. 9, movement of inner surface 26 from a deformed position (due to insert 100) back to an original position (FIG. 3) in front of (in embodiments wherein insert 100 is removed from opening 18) and/or behind bearing 14 within opening 18 securely retains bearing 14 in position within opening 18. Additionally, a spring force of portions of inner surface 26 surrounding bearing outer surface 30 may facilitate securely retaining bearing 14 within opening 18.
Securely retaining bearing 14 within opening 18 as described and illustrated herein may facilitate reducing or preventing relative movement between bearing 14 and endshield 12. As a result, noise generated by movement between bearing 14 and endshield 12 may be reduced or prevented. Moreover, vibration of bearing 14 with respect to endshield 12 that may cause bearing 14 and/or endshield 12 to wear, and may therefore possibly cause failure of bearing 14, endshield 12, or the electromagnetic device, may be reduced or prevented. Furthermore, “pound-out” of endshield opening 18 may be reduced or prevented, thereby possibly reducing or preventing noise, vibration, wear, and/or failure of bearing 14, endshield 12, and/or the electromagnetic device generally. Even further, because insert 100 and bearing 14 form a finished shape of opening 18 by deforming endshield 12, surfaces of bearing 14 (e.g., outer surface 28) and/or opening 18 (e.g., inner surface 26) may possibly be formed with less precision. As a result, a cost and/or difficulty of fabricating endshield 12 and/or bearing 14 may be reduced. For example, in some embodiments, endshield 12 is stamped from a sheet of material, which may be less time consuming and/or costly than casting endshield 12 and machining opening 18 into its finished size and/or shape. Moreover, because insert 100 deforms endshield 12, bearing 14, and for example outer surface 28 thereof, may not be deformed and/or damaged by installation into endshield 12. Still further, because interference between opening inner surface 26 and bearing outer surface 28 may facilitate reducing or preventing relative movement between bearing 14 and endshield 12, a cost and/or complexity of endshield 12 may be reduced because clamps (not shown) and/or other means may not be required to fixedly secure bearing 14 within endshield opening 18.
Although the methods and apparatus described and/or illustrated herein are described and illustrated herein with respect to an electromagnetic device, and more specifically an endshield for an electromagnetic device, the methods and apparatus described and/or illustrated herein are not limited to endshields, nor electromagnetic devices generally. Rather, the methods and apparatus described and/or illustrated herein are applicable to installing a bearing into any component. Moreover, although the methods and apparatus described and/or illustrated herein are described and illustrated herein with respect to a rotary-type bearing, the methods and apparatus described and/or illustrated herein are not limited to rotary-type bearings. Rather, the methods and apparatus described and/or illustrated herein are applicable to installation of any type of bearing.
Exemplary embodiments of methods and apparatus are described and/or illustrated herein in detail. The methods and apparatus are not limited to the specific embodiments described herein, but rather, components of each apparatus and steps of each method may be utilized independently and separately from other components and steps described herein. Each apparatus component and method step can also be used in combination with other apparatus components and/or method steps.
When introducing elements of the present invention or the preferred embodiment(s) thereof, the articles “a”, “an”, “the” and “said” are intended to mean that there are one or more of the elements. The terms “comprising”, “including” and “having” are intended to be inclusive and mean that there may be additional elements other than the listed elements.
While the invention has been described in terms of various specific embodiments, those skilled in the art will recognize that the invention can be practiced with modification within the spirit and scope of the claims.

Claims

1. A method for installing a bearing into a component using an insert, said method comprising:

aligning the insert with an opening within the component that has a dimension that is less than a complimentary dimension of the insert;

aligning the bearing with the insert;

inserting the insert at least partially into the opening such that at least a portion of a surface defining the opening is deformed by the insert; and

inserting the bearing into the opening after the insert such that the bearing is positioned at least partially within the opening and is at least partially retained within the opening by a portion of the surface defining the opening.

2. A method in accordance with claim 1 wherein said aligning the insert comprises concentrically aligning the insert with the opening and said aligning the bearing comprises concentrically aligning the bearing with the insert.

3. A method in accordance with claim 1 wherein the opening is generally open at two opposite ends thereof, said inserting the insert comprising inserting the insert into a first end of the two opposite ends and moving the insert through the opening and out a second end of the two opposite ends.

4. A method in accordance with claim 1 wherein said inserting the insert at least partially into the opening such that at least a portion of a surface defining the opening is deformed by the insert comprises elastically and plastically deforming at least a portion of the surface defining the opening.

5. A method in accordance with claim 4 wherein said inserting the insert at least partially into the opening such that at least a portion of a surface defining the opening is deformed by the insert comprises deforming the at least a portion of the surface defining the opening between about 0.0001 and 0.010 inches.

6. A method in accordance with claim 1 wherein the dimension of the opening within the component comprises a diameter and the complimentary dimension of the insert comprises a diameter.

7. A method in accordance with claim 1 wherein the dimension of the insert comprises a diameter that is substantially equal to a corresponding diameter of the bearing.

8. A method in accordance with claim 1 wherein the component comprises an endshield for an electromagnetic device and the bearing comprises a rotary-type bearing.

9. A method in accordance with claim 1 wherein the insert comprises at least one of a conical and a frustoconical shape.

10. Apparatus for installing a bearing, said apparatus comprising:

a component comprising an opening therein having two opposite open ends, said opening configured to at least partially receive the bearing; and

an insert configured to be received within said opening and having a dimension that is greater than a complimentary dimension of said opening for deforming at least a portion of a surface defining said opening when received within said opening, wherein the bearing is configured to be received within said opening and retained within said opening by at least a portion of said surface defining said opening after said insert has been at least partially received within said opening.

11. Apparatus in accordance with claim 10 wherein said opening comprises a generally cylindrical shape.

12. Apparatus in accordance with claim 10 wherein said insert is configured to plastically and elastically deform said at least a portion of said surface defining said opening when received within said opening.

13. Apparatus in accordance with claim 10 wherein the bearing is configured to be retained within said opening by elastic deformation of said at least a portion of said surface defining the opening.

14. Apparatus in accordance with claim 10 wherein said dimension of said insert comprises a diameter and said complimentary dimension of said opening comprises a diameter.

15. Apparatus in accordance with claim 10 wherein said dimension of said insert comprises a diameter that is substantially equal to a corresponding diameter of the bearing.

16. Apparatus in accordance with claim 10 further comprising said bearing.

17. Apparatus in accordance with claim 16 wherein said bearing comprises a rotary-type bearing.

18. Apparatus in accordance with claim 10 wherein said component comprises an endshield for an electromagnetic device.

19. Apparatus in accordance with claim 10 wherein said insert comprises at least one of a conical and a frustoconical shape.

20. Apparatus in accordance with claim 10 wherein said insert is configured to deform said at least a portion of said surface defining said opening between about 0.0001 inches and about 0.010 inches.