Motor grounding seal

• US 9,634,547 B1
• Filed: 02/24/2014
• Issued: 04/25/2017
• Est. Priority Date: 06/25/2005
• Status: Active Grant

• Current Assignee: Inpro/Seal LLC (Waukesha Bearings Corporation)
• Original Assignee: Inpro/Seal LLC (Waukesha Bearings Corporation)
• Inventors: Coe, Thomas D., Orlowski, David C.
• Primary Examiner(s): Nguyen, Tran
• Application Number:
  US14/188,236
• Time in Patent Office: 1,156 Days
• Field of Search: 310 68 R, 310 72, 310 85, 310219, 310220, 310221, 310248, 310249, 29596-598
• CPC Class Codes: F16C 33/80 Labyrinth sealings F16C33/761 takes precedence
• CPC Class Codes: F16J 15/4478 Pre-assembled packings
• CPC Class Codes: H02K 11/40 Structural association with grounding devices
• CPC Class Codes: H02K 5/10 with arrangements for protection from ingress, e.g. water or fingers

Abstract

A shaft seal assembly is disclosed having a stator including a main body and axial and radial projections therefrom. The rotor may be radially extended to encompass the axial and radial projections from said stator. A passageway formed between the radial projection of stator and rotor results in an axial passageway having its opening facing rearwardly from the rotor and away from the source of impinging coolant and/or contaminant. A concentric circumferential receptor groove in the stator facing the housing allows insertion of a conductive insert for transmission of electrostatic charge away from the shaft through the shaft seal assembly to the housing and ground. The receptor groove is opposite the axial passageway and provides for both a substantially lower contaminant environment and improved engagement with the conductive insert.

Claims

1. A method for extending a life of a bearing comprising:

a. providing a housing for an electric motor, wherein said housing is electrically grounded;

b. providing a shaft extending from said piece of rotatable equipment, wherein said shaft is rotatable with respect to said housing, and wherein said shaft is engaged with said electric motor;

c. positioning a said bearing within said housing, wherein said being allows said shaft to rotate with respect to said electric motor;

d. isolating said bearing from an environment external to said housing using a bearing isolator, wherein said bearing isolator is secured to said housing at a stator of said bearing isolator;

e. securing a rotor of said bearing isolator to said shaft, wherein said stator and said rotor are formed with a plurality of corresponding grooves and projections such that said stator and rotor are abutted and intermeshed with one another to form a labyrinth seal during use;

f. engaging a conductive insert with said stator, wherein said conductive insert is in electrical communication with said stator at a radially external surface of said conductive insert, and wherein said conductive insert is in electrical communication with and continually contacts said shaft at a radially internal surface of said conductive insert both when said shaft is at rest and when said shaft is rotating; and

,

g. providing a path to ground from said shaft through said bearing isolator, wherein said path passes from said housing to said stator, from said stator to a conductive insert secured to said stator, and from said conductive insert to said shaft.

2. The method according to claim 1 wherein said conductive insert is further defined as being positioned in a receptor groove fashioned in said stator.

3. The method according to claim 1 wherein said conductive insert is further defined as having a plurality of conductive brushes extending therefrom toward said shaft, and wherein said plurality of conductive brushes are in contact with said shaft.

4. The method according to claim 1 wherein a radial space between a rotor radial projection and a stator radial projection forms a first axial passage.

5. The method according to claim 4, wherein said first axial passage includes a first axial passage opening to a space in said stator and facing said housing.

6. The method according to claim 5, wherein a portion of said stator surrounds a portion of said rotor.

7. The method according to claim 1, wherein a rotor radial projection extends radially beyond any portion of said stator.

14. The method according to claim 7, wherein a rotor radial projection extends radially beyond any portion of said stator.

8. A method for simultaneously isolating a bearing and providing a path to ground away from said bearing, said method comprising:

a. providing a housing for an electric motor, wherein said housing is electrically grounded, and wherein said electric motor is positioned within said housing;

b. providing a shaft extending from said piece of rotatable equipment, wherein said shaft is rotatable with respect to said housing, and wherein said shaft is engaged with said electric motor;

c. positioning a said bearing within said housing, wherein said being allows said shaft to rotate with respect to said electric motor;

d. securing a stator of a bearing isolator to said housing;

e. providing said stator with a main body, wherein said main body of said stator is engaged with and in electrical communication with said housing;

f. providing said stator with a plurality of projections extending both axially and radially beyond said main body;

g. securing a rotor of said bearing isolator to said rotatable shaft;

h. providing said rotor with a main body;

i. providing said rotor with a plurality of projections extending both axially and radially beyond said main body, wherein said rotor projections correspond to said stator projections so as to form a labyrinth seal between said stator and said rotor; and

j. securing a conductive insert to said stator, wherein said conductive insert is in electrical communication with said stator at a radially external surface of said conductive insert, and wherein said conductive insert is in electrical communication with continually contacts said shaft at a radially internal surface of said conductive insert both when said shaft is at rest and when said shaft is rotating, and wherein said conductive insert provides said path to ground from said shaft to said conductive insert, from said conductive insert to said stator, and from said stator to said housing.

9. The method according to claim 8 wherein said conductive insert is further defined as being positioned in a receptor groove fashioned in said stator.

10. The method according to claim 8 wherein said conductive insert is further defined as having a plurality of conductive brushes extending therefrom toward said shaft, and wherein said plurality of conductive brushes are in contact with said shaft.

11. The method according to claim 8 wherein a radial space between a rotor radial projection and a stator radial projection forms a first axial passage.

12. The method according to claim 10, wherein said first axial passage includes a first axial passage opening to a space in said stator and facing said housing.

13. The method according to claim 11, wherein a portion of said stator surrounds a portion of said rotor.