一、前言 为实现电器产品标准化、系列化,希望一种设计方案只须调换几个外形尺寸相同的不同电阻的双金属片就能适用于一个宽广的电流容量范围,满足不同额定电流的电器产品的要求。在不考虑环境温度的条件下,一定牌号的电阻型热双金属(通常简称为电阻双金属)弯曲的程度取决于所产生焦耳热的大小,Q=0.24I~2Rt。若要求在相同时间里产生的热效应相等,即t,Q为常数,由于R=ρ1/s,所以ρ∝1/I2或I∝(?),此式得出了双金 I. Preface To realize the standardization and serialization of electrical products, we hope that a design solution can be applied to a wide range of current capacity by simply changing several bimetallic sheets with the same resistance and different external dimensions, so as to satisfy different rated current electrical products Request. Regardless of the ambient temperature, the degree of bending of a given grade of resistive hot bimetal (often referred to as resistive bimetal) depends on the magnitude of Joule heat generated, Q = 0.24I ~ 2Rt. If the thermal effects at the same time are required to be equal, that is, t and Q are constants, since R = ρ1 / s, ρα1 / I2 or Iα (?)