Abstract: The turnout starting circuit of ZYJ7 type point machine in railway speed-increasing section is improved, and an integrated phase breaker (DBQ) with time-delay breaking function is designed to cut off the motor starting circuit at the specified time, so as to prevent the turnout action not to be in place due to failure, no indication after in place and jamming phenomenon. It can save a time relay and simplify the starting circuit in accordance with the fail-safe principle.

Key words: ZYJ7-type point machine, speed-increasing turnout, starting circuit, timing circuit

摘要： 对铁路提速区段ZYJ7型转辙机道岔的启动电路进行改进，设计带有延时切断功能一体断相保护器（DBQ），在规定时间切断电机启动电路，防止道岔动作故障没有到位、到位后无表示、卡阻现象。在满足故障导向安全原则下节省一个时间继电器，简化启动电路。

关键词: ZYJ7转辙机, 提速道岔, 启动电路, 定时电路