一、前言我国的热处理炉普遍使用位式调节仪表,这种仪表采用微动开关或电接点的通断动作来控制炉子的通电功率,由于被调系统的惯性和滞后,以及微动开关存在控制动作不灵敏区,炉温波动较大,不能刚好恒温在给定点上。所以有必要提高控温精度。提高控温精度的方案大致有两类:一类是淘汰位式调节系统,采用 Preface China’s heat treatment furnace commonly used position adjustment instrument, this instrument uses micro-switch or electrical contacts on and off action to control the furnace power, due to the inertia and delay of the system being transferred and the existence of micro-switch control Motion insensitive zone, furnace temperature fluctuations, can not just constant temperature at a given point. So it is necessary to improve the temperature control accuracy. There are two kinds of schemes to improve the accuracy of temperature control: one is to eliminate the position adjustment system and adopt it