Tapered-Thickness Bimetal

The most important properties of thermostatic bimetal strips of uniformly tapered width or thickness or both have been analyzed mathematically, and the findings are described in this paper. A tapered-thickness form is found to be the best practical one from the standpoint of economy of material. Conveniently usable charts are included which are applicable in the form of correction coefficients to the standard formulas for thermostatic deflection and mechanical deflection of strips of uniform thickness and width. The dual-tapered form is especially useful in reducing vibration troubles in slow-acting thermostats, and formulas are given for determining the fundamental frequency of single- or dual-tapered strips of any taper ratio.