QUARTZ COIL SPRING AND METHOD OF PRODUCING THE SAME

摘要

A quartz coil spring which has a spiral coil formed of a quartz band. A mandrel bar having a length greater than the predetermined overall length of the coil spring is coaxially disposed in a preliminarily prepared quartz tube. Thermoplastic wax is charged into a space between the mandrel bar and the inner wall of the quartz tube and solidified, the space being filled with the wax filler. The quartz tube is rotated together with the wax filler around the axis by rotatively driving the mandrel bar. The quartz tube being rotated is spirally cut with a predetermined width from the outer peripheral surface by a rotatry cutter disc, thereby forming a spiral coil body. The wax filler is melted for removal by thermal treatment, whereby the spiral coil is released from the mandrel bar. The released spiral coil is immersed in a bath containing fluorinated acid and etched until a predetermined band thickness is obtained.