曝光时间控制器,是自动控制曝光时间用的。晒图纸放好后,达到预定时间(2分30秒～3分),发出讯响信号(15秒),即可取图。如不取,15秒后,自动停电灭灯,免出废图。工作原理如下:该装置采用两个电子管式时间继电器(由DJS—41型稍加改装而成)和装在晒图机台面上的微动开关LX组成计时装置(图4)。操作时,摆好图纸,放下压盖,LX动作计时开始。到规定时间后,灵敏继电器J_1动作,其常开接点 The exposure time controller is used to automatically control the exposure time. After the drying paper is laid down, the scheduled time (2 minutes 30 seconds to 3 minutes) is reached, and a beep signal (15 seconds) is issued. If not taken, after 15 seconds, the automatic blackout will turn off the lights, avoiding waste drawings. The working principle is as follows: The device is composed of two electron tube type time relays (slightly modified by the DJS-41 type) and a microswitch LX installed on the surface of the blueprint machine (Figure 4). During operation, set the drawings, put down the cover, and start the LX operation timing. After the specified time, the sensitive relay J_1 operates and its normally open contact