Method of winding pre-twisted wires in optical cable

Pre-twisted wires in optical cables are wound using precision-controlled automated systems that manage tension, traverse speed, and spool geometry to ensure uniform, high-quality coils.

Winding Principles

Winding pre-twisted wires or optical fibers requires precise control of tension and positioning to prevent damage and maintain cable integrity. The wire is guided onto a bobbin or spool using a final pulley or traverse mechanism, which moves the wire back and forth along the spool's axis to create uniform layers . For tapered bobbins, the inner surface of the flange is inclined, allowing more fiber to be wound per bobbin while requiring careful control of the bobbin's position relative to the guiding pulley .

Automated Precision Winding

Modern optical cable production uses fully automated precision winding machines. These systems include:

• High-resolution electrical drives and mechatronic modules for exact positioning of the wire .
• Non-contact coil scanners to detect geometry and flange positions, ensuring perfect alignment on conical or semi-conical spools .
• Bidirectional winding capability to maintain consistent coil density and prevent wire crossings .
• Electronic linear traversing systems to control traverse speed and delay angles, optimizing the winding pattern for different spool types .

Tension and Speed Control

Maintaining consistent tension is critical to avoid stretching or damaging the pre-twisted wires. Machines use dancer accumulators, capstans, and tension controllers to regulate the wire during winding . High-speed rewinding machines can operate at speeds up to 1000 m/min, allowing long lengths of fiber or wire to be wound efficiently while preserving quality .

Advantages of Automated Winding

• Eliminates manual guiding, reducing labor and safety risks .
• Ensures side-by-side placement of wires without gaps or overlaps .
• Supports various spool geometries, including H-spools, conical, and custom designs .
• Provides real-time monitoring and adjustment for high-precision applications, such as fiber Bragg gratings or sensitive optical sensors .

Summary

The method of winding pre-twisted wires in optical cables combines mechanical guidance, automated traverse control, tension regulation, and real-time monitoring. Using tapered or conical bobbins, high-speed rewinding machines, and precision coiling units ensures uniform, high-quality winding suitable for industrial-scale optical cable production .