Explosion-proof current diverting device

Abstract

A bearing isolator and explosion-proof current diverting device may be configured to dissipate an electrical charge from a rotating piece of equipment to ground, such as from a motor shaft to a motor housing. One aspect of an explosion-proof current diverter ring may include 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. A conductive assembly may be positioned in a radial bore formed in the stator such that the conductive assembly contacts the rotor to conduct electricity from the shaft to the housing through the explosion-proof current diverting device. The explosion-proof current diverting device may be configured to define a flame path to achieve various explosion-proof certifications.

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,   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, 
 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 first interface is further defined as being filled with an inert material, and 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 . An explosion-proof current diverting device comprising:
 a. a stator configured for engagement with an equipment housing, wherein said stator is in electrical communication with said equipment housing, said stator comprising:
 i. a main body; 
 ii. a radial bore extending from a radially exterior surface of said stator to a radially interior surface of said stator; 
   b. a rotor configured for engagement with a shaft extending from and rotatable with respect to said equipment housing, wherein said rotor is in electrical communication with said shaft, wherein a portion of said rotor is positioned between said stator and said shaft, wherein said rotor comprises a main body, and wherein a portion of a radially exterior surface of said main body is positioned adjacent said radial bore in said stator;   c. a conductive assembly positioned in said radial bore, wherein said conductive assembly is in electrical communication with said stator, and wherein a contact portion of said conductive assembly extends radially inward beyond said radially interior surface of said stator and physically contacts said radially exterior surface of said rotor;   d. a flame path from an area in said equipment housing to an area external with respect to said explosion-proof current diverting device, wherein said flame path is defined by a first axial interface between said stator and said rotor and a first radial interface between said stator and said rotor.   
     
     
         13 . The explosion-proof current diverting device according to  claim 12  further comprising a stator cap, wherein said stator cap is selectively engagable with an exterior surface of said stator, and wherein said stator further comprises an annular stator radial groove in an inner diameter of said stator adjacent said radial bore. 
     
     
         14 . The explosion-proof current diverting device according to  claim 13  wherein said stator cap is further defined as covering a radially exterior opening of said radial bore when said stator cap is engaged with said stator. 
     
     
         15 . The explosion-proof current diverting device according to  claim 14  further comprising a rotor cap, wherein said rotor cap is selectively engagable with an exterior surface of said rotor. 
     
     
         16 . The explosion-proof current diverting device according to  claim 15  wherein said rotor cap further comprises an axial projection, wherein said axial projection of said rotor cap extends over a radial projection formed in said stator. 
     
     
         17 . The explosion-proof current diverting device according to  claim 16  wherein said rotor cap further comprises an axial groove, wherein said axial groove in said rotor cap corresponds to an axial projection formed in said rotor. 
     
     
         18 . The explosion-proof current diverting device according to  claim 17  wherein said rotor cap is engaged with said rotor via a first mechanical fastener, and wherein said stator cap is engaged with said stator via a second mechanical fastener. 
     
     
         19 . The explosion-proof current diverting device according to  claim 18  wherein said rotor further comprises a radial projection, wherein said radial projection in said rotor corresponds to a radial groove in said stator. 
     
     
         20 . A method of preventing an explosion, said method comprising:
 a. engaging an explosion-proof current diverting device with an equipment housing, wherein a rotatable shaft extends from said equipment housing, and wherein a portion of said shaft is positioned within said explosion-proof current diverting device;   b. defining a flame path within said explosion-proof current diverting device via at least one interface between a first portion of said explosion-proof current diverting device that is rigidly secured to said equipment housing and a second portion of said explosion-proof current diverting device that is engaged with said first portion; and,   c. configuring said first portion to engage at least one conductive assembly, wherein said conductive assembly is configured to contact a rotor engaged with said shaft on a portion of said rotor that is positioned within said explosion-proof current diverting device, and wherein said conductive assembly is configured to conduct electric current from said shaft to said first portion of said explosion-proof current diverting device.