初搞维修工作的同志,常常感到怎样迅速地找到邮政机械电控部分的故障所在,是一大难题,本文就这个问题谈一点体会。一、介绍一种通用框图邮政机械多半是数字电路控制的专用机械。它的电控部分,虽然千差万别,但不外乎由图1中示出的几个部分组成:脉冲变换电路、咏冲计数和显示电路、译码和执行驱动电路、执行机构和附属电路。例如对邮票出售机来 Comrades engaged in maintenance work often feel how to quickly find the postal machinery and electronic control part of the fault lies, is a major problem, this article talk about this issue a little experience. First, introduce a common block diagram Postal machinery is mostly digital circuit control of special machinery. Its electrically controlled parts, though vastly different, are nothing more than the ones shown in Figure 1: a pulse converter, a pulse counting and display circuit, a decoder and driver circuit, an actuator and ancillary circuits. For example, a stamp sale machine came