今年5月5日，北京玉泉营环岛家具城发生火灾，两个小时的熊熊烈火，使一座两万多平方米的营业大厅及展销家具化为灰烬。经北京市消防局调查，认定是电铃着火引燃沙发成灾的。电铃怎么会着火呢？电铃的工作原理是，当电铃线圈有电流通过时，产生磁场，把衔铁吸过来，带动铃锤敲? On May 5th this year, a fire broke out in the furniture town of Huquanying in Beijing, and a two-hour raging fire caused a 20,000-square-meter business hall and furniture for exhibitions to become ashes. After investigation by the Beijing Municipal Fire Bureau, it was determined that the fire of the electric bell ignited the sofa. How can the bell catch fire? The working principle of the bell is that when the electric current passes through the bell coil, a magnetic field is generated, and the armature is sucked in and the bell hammer is knocked on.