Self-compensating spiral spring for a mechanical balance-spiral spring oscillator

摘要

This self-compensating spiral spring for a mechanical balance-spiral spring oscillator for a watch or clock movement or other precision instrument, made of an Nb-Hf paramagnetic alloy possessing a thermal coefficient of Young's modulus (TCE), such that it enables the following expression to be substantially equal to zero: 1 $\frac{1}{E}it\frac{dE}{dT}+3it{\mathrm{alpha}}_s-2it{\mathrm{alpha}}_b$ where: E: Young's modulus of the spiral spring of the oscillator; 2 $\frac{1}{E}it\frac{dE}{dT}=TititCititE=\begin{array}{c}\mathrm{thermal}itit\mathrm{coefficient}itit\mathrm{of}itit\mathrm{Young}\text{'}itsit\\ it\mathrm{modulus}itit\mathrm{of}itit\mathrm{the}itit\mathrm{spiral}itit\mathrm{spring}it\\ it\mathrm{of}it\end{array}$