单相异步电动机过热保护电路的设计

Design of Overheat Protection Circuit for Single-Phase Non-Asynchronous Motor

针对学生电工实习中使用的台电钻,经常因为短时工作制的、连续运行时间不得超过60min的封闭式电动机做连续运行,其带载能力大大下降使电动机过热而烧毁的缺点,对原来电路进行了重新设计。设计后的电路,可将不同工作制的电动机相互代用,为学校节省了部分资金。实验结果证明,该电路不仅实现了单相异步电动机的过热保护,而且电路设计简单,便于操作、维护和维修。

As to electric drills that students use in practicing, this paper proposes improving the original circuit to protect the motor damaged when overheating. The drills are designed of short- time work system, and the continual running time must not surpass 60min. When the closed type motor does continuously move, its belt carry capacity greatly drops, which results in overheat and destroys the electric motor by burning. We have carried on the redesign to the original electric circuit. The newly designed electric circuit may substitute mutually the different working system electric motor, which has saved funds for the school. The result shows that this method can overcome phase fault and the new design of circuit is simple, easy to operate and repair.