Electrical grounding apparatus and method and washer for use therewith

• US 3,914,001 A
• Filed: 12/26/1973
• Issued: 10/21/1975
• Est. Priority Date: 12/26/1973
• Status: Expired due to Term

• Current Assignee: Donald A. Fauth, Warren J. Nelson
• Original Assignee: Donald A. Fauth, Warren J. Nelson
• Inventors: Nelson, Warren J., Fauth, Donald A.
• Primary Examiner(s): McGlynn, Joseph H.
• Assistant Examiner(s): Desmond, E. F.
• Application Number:
  US05/428,005
• Time in Patent Office: 664 Days
• Field of Search: 339/95A,115C,114,14R
• US Class Current: 439/92
• CPC Class Codes: H01R 4/64 Connections between or with conductive parts having primarily a non-electric function, e.g. frame, casing, rail
• CPC Class Codes: Y10S 439/927 Conductive gasket

Abstract

An electrical grounding apparatus and method of making the same is provided comprising a plurality of electrically conductive aluminous strips arranged in a grid-like pattern having a plurality of areas of intersection. An electrically conductive washer is provided at each area of intersection and a fastener is used to hold an associated pair of strips at each area of intersection against opposed surfaces of the washer; and, the washer has a thickness which is sufficient to separate the strips and prevent crevice corrosion and has a pair of opposed surfaces with projections extending therefrom which bite into an associated conductor upon tightening the fastener to hold the washer sandwiched between the strips and thereby assure an optimum electrical connection between the associated pair of strips.

Claims

1. An electrical grounding system adapted to be buried underground and comprising, a plurality of electrically conductive strips arranged in a grid-like pattern and having a plurality of areas of intersection and wherein immediately adjacent pairs of strips at each area of intersection are arranged transverse each other, a set of aligned openings in an associated pair of said strips at each of said areas of intersection, a plurality of electrically conductive washers corresponding in number to said plurality of areas of intersection with each washer being arranged between the associated pair of strips at its area of intersection and each washer having an opening therethrough which is aligned with an associated set of aligned openings and having an outside surface, a plurality of fasteners corresponding in number to said plurality of areas of intersection with each fastener extending through the associated set of openings and the opening in its associated washer, each of said fasteners holding the associated strips at its area of intersection in sandwiched relation against its associated washer, each washer having a thickness which is sufficient to separate said strips and minimize crevice corrosion and having a pair of opposed surfaces, each of said opposed surfaces having projections extending therefrom Which bite into an associated strip upon tightening the associated fastener to hold the washer sandwiched between its strips at the associated area of intersection to thereby assure a substantially resistance free electrical connection between said strips at each area of intersection, said projections extending from each surface of each washer being arranged in a continuous spiral pattern from each washer opening to its outside surface with said projections defining an unobstructed spiral channel from the center portion of the washer to the outside thereof, each spiral projection having a substantially V-shaped configuration including a sharp apex enabling easy biting thereof into an associated strip, said biting providing an indentation and freshly exposed metal free of an oxide coating, and each V-shaped spiral projection having a vertical height which is roughly one-half the radial distance between the apexes of immediately adjacent projections, said vertical height assuring forming of said indentation as well as assuring said unobstructed spiral channel.

2. A system as set forth in claim 1 and further comprising an electrically conductive joining compound between each of said opposed surfaces and its associated strip, said compound helping to make the joint air and moisture tight while preventing corrosion between adjacent surfaces, and said spiral channel assuring that excess compound flows outwardly from the center of an associated washer at an associated area of intersection to assure said biting.

3. A system as set forth in claim 1 in which each of said strips, washers, and fasteners is made of aluminous material.

4. A system as set forth in claim 3 in which each of said strips has a rectangular cross-sectional configuration.