电梯的安全保护系统包括机械安全保护装置和电气安全保护装置两大部分~([1])。电梯门锁啮合深度的检测是电梯门安全检测中的一项重要内容。据统计,80%以上的电梯故障和70%以上的电梯事故都是因为电梯的门系统出现问题而引起的~([2])。美国、日本、欧洲等发达国家和地区高度重视电梯门及门区安全技术的研究、测试、分析等。在国内,门锁啮合深度检测的工具比较落后,通常采用卡尺进行测 Elevator safety protection system includes mechanical safety protection device and electrical safety protection device two parts ~ ([1]). Elevator door lock engagement depth detection is an important part of elevator door safety testing. According to statistics, more than 80% of the elevator failures and more than 70% of the elevator accidents are caused by the elevator door system problems caused by ~ ([2]). The United States, Japan, Europe and other developed countries and regions attach great importance to elevator door and door area security technology research, testing, analysis. In China, the depth of the door lock engagement detection tools are relatively backward, usually measured with a caliper