Apparatus and methods for line stringing

• US 4,421,301 A
• Filed: 04/01/1982
• Issued: 12/20/1983
• Est. Priority Date: 12/13/1979
• Status: Expired due to Term

• Current Assignee: Claude L. Chapman
• Original Assignee: Claude L. Chapman
• Inventors: Chapman, Claude L.
• Primary Examiner(s): Watson, Robert C.
• Application Number:
  US06/364,529
• Time in Patent Office: 628 Days
• Field of Search: 254/139.3 R, 254/134.3 PA
• US Class Current: 254/134.30R
• CPC Class Codes: H02G 1/04 for mounting or stretching

Abstract

The problem of stringing power transmission lines via a line-holding structure that has an upper cross support and no side access, such as the center strand under a cross support on a tower, is solved by the methods and apparatus disclosed. The stringing apparatus is carried in a depending manner from the aircraft by a hoist line and enables the insertion of a sock line through the line-holding structure, followed by the pulling of the line therethrough. Different forms of the stringing apparatus enable an insertion with a needle-type structure, a pull-push structure, a pivoting gate structure, and a rotary annular carrier or ring segment structure. After the sock line has been strung, one end is secured to a power line which is then threaded through the line-holding structure to complete the stringing of a center strand of power line.

Claims

1. A method of aerially stringing a threading line through a series of towers comprising the steps of:

connecting the lower end of a hoist line to a stringing member to suspend the stringing member from the hoist line and an aircraft;

connecting a threading line to the stringing member and maintaining the threading line taut to keep the stringing member in a generally straight-ahead position while suspended by the aircraft; and

advancing the stringing member and attached threading line through a window-like line-holding structure on a tower by manipulation solely from the upper end of the hoist line while being suspended continuously from above by said hoist line while maintaining the threading line taut without changing the length of the threading line, and repeating said advancing for each successive tower without changing stringing members for each successive tower through which said threading line is advanced.

2. A method as set forth in claim 1 wherein said advancing is by a pull stroke applied to said threading line.