Electrical fitting for easy snap engagement of cables

• US 6,682,355 B1
• Filed: 01/21/2003
• Issued: 01/27/2004
• Est. Priority Date: 01/15/1998
• Status: Expired due to Term

• Current Assignee: Arlington Industries Incorporated
• Original Assignee: Arlington Industries Incorporated
• Inventors: Gretz, Thomas J.
• Primary Examiner(s): Ta, Tho D.
• Assistant Examiner(s): TSUKERMAN, LARISA Z
• Application Number:
  US10/348,111
• Time in Patent Office: 371 Days
• Field of Search: 439/92, 439/95, 439/98, 174/65.R, 174/51
• US Class Current: 439/98
• CPC Class Codes: H02G 15/04 Cable-end sealings
• CPC Class Codes: H02G 3/0616 Joints for connecting tubing to casing
• CPC Class Codes: H02G 3/0691 Fixing tubing to casing by auxiliary means co-operating with indentations of the tubing, e.g. with tubing-convolutions
• CPC Class Codes: H02G 3/083 Inlets
• CPC Class Codes: H02G 3/18 providing line outlets
• CPC Class Codes: H02G 3/22 Installations of cables or lines through walls, floors or ceilings, e.g. into buildings

Abstract

An electrical fitting that enables easy snap-in engagement of armored cable to an electrical panel. The fitting comprises a hollow, tubular, electrically conductive housing including a fastening arrangement on the leading end to allow snap-in engagement to a panel. A resilient, electrically conductive, generally cylindrical-shaped split ring is secured within the trailing end of the housing and includes a plurality of locking tangs lanced longitudinally and bent inwardly to a smaller diameter than the outer diameter of the armored cable that the fitting will be used in conjunction with. Edges of the locking tangs are staggered longitudinally within the tubular connector to enable each tang to engage a trough in the surface of the armored cable. The tight engagement of the locking tangs to the trough areas of the cable provide good surface contact between the locking tangs and the cable, thereby improving continuity and lowering the millivolt drop between the cable, the fitting, and the panel.

Claims

1. A fitting for securing cable to a panel comprising:

a tubular housing including a leading end, a trailing end, a central bore, and an inner peripheral wall at said trailing end;

a fastening arrangement on said leading end for securing said housing to an aperture in said panel;

a resilient, electrically conductive, generally cylindrical ring inserted within said central bore in said trailing end of said housing, said ring having a trailing edge;

an arrangement at said trailing end of said housing and said ring assembled in a manner to resist removal of said ring from said housing;

a locking tang lanced from said ring which is bent inwardly from said ring and having a free end; and

a recess in said inner peripheral wall of said housing at said trailing end, with said recess in alignment with said locking tang of said ring to provide a space into which said locking tang may be received when forced outward.

2. The fitting of claim 1 wherein said ring includes a total of two or more of said locking tangs.

3. The fitting of claim 2 wherein said free ends of said locking tangs are at staggered distances with respect to said trailing edge.

4. The fitting of claim 1 wherein said split snap ring is formed of spring steel to a thickness of between 0.010 and 0.030 inch.

5. The fitting of claim 4 wherein said spring steel is AISI (American Iron and Steel Institute) 1050 CRS (cold rolled steel), annealed #3 edge, hardened to a Rockwell C hardness of between 42 and 44.

6. The fitting of claim 1 wherein said fastening arrangement includes a seat on said leading end of said housing and an electrically conductive forward split ring disposed on said seat, said forward split ring including tangs for engaging the walls of said panel.

7. The fitting of claim 6 wherein said fastening arrangement includes forward tangs for engaging said panel and grounding tangs for biasing against the walls of said aperture in said panel for providing good electrical continuity between said panel and said housing.

8. The fitting of claim 1 wherein said arrangement at said trailing end includes

one or more outward-directed tangs lanced longitudinally from said split snap ring, said outward-directed tangs including a leading end cantilevered from said split ring and a free trailing end; and

a complementary number of slots in said trailing end of said housing, whereby compression and insertion of said resilient split snap ring into said trailing end of said housing enables said outward-directed tangs to engage said slots.

9. The fitting of claim 1 wherein said arrangement at said trailing end includes an annular flange at said trailing end of said housing, said annular flange extending into said central bore, said annular flange capturing said resilient split snap ring and securing it therein when said ring is compressed and inserted therein.

10. The fitting of claim 1 wherein said fastening arrangement includes a threaded nose on said leading end of said housing and a threaded lock nut on said threaded nose for engaging the walls of said panel.

11. The fitting of claim 1 wherein said locking tangs extend from said inner peripheral wall of said housing at a first angle of preferably between 10°

and 30°

with respect to the wall and with the free end at a greater angle of preferably between 50° and

70°

with respect to the wall.

12. The fitting of claim 1 wherein said free ends of said locking tangs include sharp edges.

13. A method for quickly connecting armored cable to an aperture in a panel, comprising:

providing an electrically conductive panel with an aperture;

providing an armored cable;

providing a tubular, hollow, electrically conductive housing having a leading end for insertion in said aperture, a trailing end for connection to said armored cable, and a face limiting the distance said leading end may be inserted in said hole;

providing an electrically conductive forward snap ring secured to said leading end of said connector with said forward snap ring having a leading portion and a trailing portion;

providing at least one panel forward tang on said forward snap ring that has a relaxed outer dimension greater than the diameter of said aperture;

providing at least one grounding tang integral with and supported at one end from said forward snap ring and free at its opposite end; and

providing a generally cylindrical-shaped electrically conductive split ring secured to said trailing end, said split ring including inward extending locking tangs;

inserting said leading end of said electrical housing with said forward snap ring into said aperture until said crest of said forward tang clears said aperture and said grounding tang draws said face of said electrical connector against said junction box; and

inserting said armored cable into said trailing end of said housing containing said split snap ring until each of said locking tangs engage a trough area on the outer surface of said armored cable.