论文部分内容阅读
我们在常压灭菌灶的使用过程中,试制了一种温控简易报警器,经过二年来的安装使用,效果良好。一、工作原理简易报警器的线路见图1.由两只三极管与C1、C2组成音频振荡器,振荡器信号通过喇叭发出。调节R的阻值可改变音频频率。B是恒温控制温度计,也是电路的电源开关。当达到预定温度时,电路接通,振荡器工作,发出报警音频信号;温度未达到预定要求时,振荡器电源是断开的,所以振荡器不工作。图1中BG1、BG2组成互补电路,要求一个用PNP型晶体管,一个用NPN型晶体管,它们的放大值大于20就可以了,R取
We use the pressure in the process of sterilization, trial production of a temperature control simple alarm, after two years of installation, the effect is good. First, the working principle Simplified alarm circuit shown in Figure 1. By the two transistors and C1, C2 audio oscillator, the oscillator signal sent through the speaker. Adjust the resistance of R can change the audio frequency. B is a thermostat control thermometer, but also the circuit’s power switch. When the predetermined temperature is reached, the circuit is turned on, the oscillator is working, and the alarm audio signal is sent out. When the temperature does not reach the predetermined requirement, the power to the oscillator is off and the oscillator does not operate. Figure 1, BG1, BG2 complementary circuit, requiring a PNP transistor, a NPN transistor, their amplification is greater than 20 on it, R