Current Diverter Ring

• US 20140183998A1
• Filed: 06/18/2013
• Published: 07/03/2014
• 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: Hoehle, Neil F., Tejano, Robert A., Orlowski, David C., Vicars, Dwight A.
• Granted Patent: US 9,071,092 B2
• Time in Patent Office: Days
• US Class Current: 310/88
• CPC Class Codes: F16J 15/4478 Pre-assembled packings
• CPC Class Codes: H01R 39/10 other than with external cylindrical contact surface, e.g. flat slip-rings
• CPC Class Codes: H01R 39/12 using bearing or shaft surface as contact surface
• CPC Class Codes: H01R 39/64 Devices for uninterrupted current collection
• CPC Class Codes: H02K 11/40 Structural association with grounding devices
• CPC Class Codes: H02K 5/136 explosion-proof
• CPC Class Codes: H02K 5/1732 radially supporting the rotary shaft at both ends of the rotor H02K5/1737 takes precedence

Abstract

The current diverter rings (CDRs), captured CDRs, bearing isolators, and explosion-proof CDRs serve to dissipate an electrical charge from a rotating piece of equipment to ground, such as from a motor shaft to a motor housing. One embodiment of the explosion-proof CDR includes a stator that may be mounted to the equipment housing and a rotor that may be mounted to a shaft. The rotor may rotate with the shaft may be encompassed by stator and a cap, which cap may be secured directly to the stator or the housing. A conductive assembly may be positioned in a radial channel formed in the stator such that the conductive assembly contacts the shaft to conduct electricity from the shaft to the housing. Another embodiment of an explosion-proof CDR does not require a rotor. The explosion-proof CDR may be configured to define a flame path to achieve various explosion-proof certifications.

Claims

1. An explosion-proof CDR comprising:

a. a cap configured for engagement with a housing, wherein said cap is formed with a cap body having a central bore to accommodate a portion of a shaft extending from said housing, and wherein said cap body includes at least one body radial bore extending into said central bore;

b. a stator configured for engagement with said cap, wherein said stator is formed with a central bore to accommodate a portion of said shaft, and wherein said stator is formed with an axial projection extending toward said cap and positionable over a portion of said cap body; and

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c. a conductive assembly positioned in said at least one body radial bore, wherein said conductive assembly and said cap are configured such that a portion of said conductive assembly contacts said shaft.

2. The explosion-proof CDR according to claim 1 further comprising a sleeve configured for engagement with said shaft, wherein said conductive assembly and said cap are configured such that a portion of said conductive assembly contacts said sleeve, and wherein said conductive assembly is configured to conduct electric current from said sleeve to said cap.

3. The explosion-proof CDR according to claim 2 wherein said at least one body radial bore is further defined as a plurality of body radial bores, and wherein said explosion-proof CDR further comprises a plurality of conductive assemblies corresponding to and respectively positioned in said plurality of body radial bores such that a portion of each said conductive assembly contacts said sleeve.

4. The explosion-proof CDR according to claim 3 further comprising a plurality of plugs corresponding to and respectively position in said plurality of body radial bores, wherein each said plug is radially distal with respect to each said conductive assembly.

5. The explosion-proof CDR according to claim 4 wherein said cap body further comprises a cap groove formed adjacent the axially distal portion thereof, wherein a portion of said cap groove faces said sleeve, and wherein said cap groove is configured to intersect the radially inward end of said plurality of body radial bores.

6. The explosion-proof CDR according to claim 5 wherein said stator further comprises a stator groove positioned axially adjacent a proximal portion of said axial projection, and wherein a portion of said stator groove faces said sleeve.

7. The explosion-proof CDR according to claim 6 wherein said cap body further comprises a cap axial projection on a distal end of said cap body, wherein said cap axial projection is configured to fit within a portion of said stator groove during operation of said explosion-proof CDR.

8. The explosion-proof CDR according to claim 7 further comprising:

a. a first interface between said cap and said housing;

b. a second interface between said sleeve and said cap;

c. a third interface between said sleeve and said stator; and

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d. a plurality of interfaces between said cap and said stator, wherein said first, second, third, and said plurality of interfaces are configured such that a flame path is defined outward from said explosion-proof CDR.

9. The explosion-proof CDR according to claim 8 wherein said flame path is further defined as complying with a predetermined standard for non-sparking and/or intrinsically safe applications.

10. The explosion-proof CDR according to claim 9 wherein said sleeve further comprises at least one sleeve groove on a radially interior surface thereof, wherein at least one o-ring is positioned in said at least one sleeve groove and configured to engage said sleeve with said shaft such that said sleeve rotates therewith.

11. The explosion-proof CDR according to claim 10 wherein said cap is further defined as being engaged with said housing via at least one fastener, and wherein said stator is further defined as being engagable with said cap via a least one fastener.

12. The explosion-proof CDR according to claim 11 wherein said first interface is further defined as being filled with an inert material.

13. The explosion-proof CDR according to claim 12 wherein said plurality of body radial bores is further defined as six body radial bores.

14. An explosion-proof CDR comprising:

a. a stator configured to be engaged with a housing, wherein said stator is formed with a stator groove therein, wherein said stator is formed with a central bore, and wherein said stator is formed with at least one radial bore;

b. a rotor configured to be engaged with a shaft protruding from said housing, wherein said rotor is formed with a central bore to accommodate a portion of said shaft, wherein said rotor is configured to cooperate with said stator groove, and wherein a portion of said rotor is exposed to a radially inward portion of said at least one radial bore in said stator;

c. at least one conductive assembly engaged with said at least one radial bore, wherein a portion of said at least one conductive assembly is positioned such that a portion thereof contacts said rotor;

d. a cap configured to be engaged with said stator, wherein said cap cooperates with said rotor and said stator groove to form a plurality of interfaces between said rotor and said cap.

15. The explosion-proof CDR according to claim 14 wherein said plurality of interfaces are further defined as being configured such that a flame path is defined outward from said explosion-proof CDR.

16. The explosion-proof CDR according to claim 15 wherein said flame path is further defined as complying with a predetermined standard for non-sparking and/or intrinsically safe applications.

17. The explosion-proof CDR according to claim 16 wherein said rotor further comprises a plurality of o-ring channels on a radial interior surface of said central bore, wherein a corresponding o-ring is positioned in each said o-ring channel and configured to securely engage said rotor with said shaft such that said rotor rotates therewith.

18. A method of preventing an explosion, said method comprising:

a. engaging an explosion-proof CDR with a housing, wherein a rotatable shaft extends from said housing, and wherein a portion of said shaft is positioned within said explosion-proof CDR;

b. defining a flame path within said explosion-proof CDR via at least one interface between a first portion of said explosion-proof CDR that is rigidly secured to said housing and a second portion of said explosion-proof CDR that is engaged with said first portion; and

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c. configuring said first portion to engage at least one conductive assembly, wherein said conductive assembly is configured to contact a surface of said shaft on said portion of said shaft positioned within said explosion-proof CDR, and wherein said conductive assembly is configured to conduct electric current from said shaft to said first portion of said explosion-proof CDR.

19. The method according to claim 18 wherein said explosion-proof CDR further comprises a plurality of conductive assemblies.

20. The method according to claim 19 wherein said explosion-proof CDR further comprises a sleeve, wherein said sleeve is engaged with said shaft such that said sleeve rotates therewith, and wherein said plurality of conductive assemblies are configured to contact said sleeve.