As the race to fulfill the ever-increasing demand for fiber optic assemblies began, the need for a fully automatic assembly line has come into focus. Individual filaments must be connected in such a way that the light traveling from strand to strand is not degraded. Owens Design (Fremont, CA) developed the custom Fiber Optic Assembly Line to join optic fibers and connectors. Using SMC’s (Indianapolis, IN) Series VQ5000 5-port solenoid valve as part of the feeder system, the assembly produces five types of fiber optic transducers.
The Fiber Optic Assembly Line, 4 × 15' to produces 4,000 units per hour. The Series VQ5000 valve is utilized as part of the assembly’s pneumatic fiber optic connector component part feeder system, the VQ5000 are part of the subsystem that supply air to the feeders. This system feeds constituent parts (two to four, depending on type) to a pick-and-place Selective Compliant Articulated/Assembly Robot Arm (SCARA). The SCARA is a 4-axis industrial robot able to receive components regardless of their type or shape. Each feeder is designed to handle a different connector type. Components are stored in tubes which via gravity feeds to the feeding device, which in turn feeds the SCARA.
Fiber optic filaments are notorious for their sensitivity to contaminants and damage; such defects change the geometrical propagation patterns of light in the fiber and cause scattering. Any cut must be a clean cleave. Having a connector system that conducts the entire process in a clean, enclosed unit was ideal. The industrial design of the machine was critical as the client was developing funding sources and planned to OEM the system.
An optical fiber connector constitutes a fiber-to-fiber interconnection and aligns the fiber core of two like optical fibers. There are different styles of connectors in the industry. The primary difference between connectors is in the dimensions and the mechanical grip. Most fiber optic connectors use a coupling device such as an alignment sleeve. The Fiber Optic Assembly Line utilizes three, the LC (Local Connector), SC, and FC. The FC, or Ferrule Connector, has a floating ferrule (a circular clamp used to hold, align, and attach fibers, wires or, on a larger scale, posts) providing mechanical isolation. An FC comes into contact with the optic fiber, whereas the SC (Standard Connector) has a push-pull design the resists fiber end-face contact damage during connection.
Initially, “raw” fiber optic is fed to the assembly, where the ends of the fiber optic cord are stripped of their protective jackets. Through the whole assembly device is a palletized conveyor system, carrying components to the several modules that compose the assembly. The first is the assembly module, where the SCARA robot (and the SMC valves) receives components from the dedicated parts feeders. The second module for alignment, wherein the different components are lined up, bonded to the fiber, and optic fiber’s tip is trimmed. Thirdly is the polishing module, where the tip is polished to a mirror finish. The connector mechanism is the final stage of construction.