电动伸缩门的基本组件是导轨、滑轮及传动皮带。由于这三个部分与电动伸缩门的运行直接有关，是电动伸缩门正常使用条件下的易损件，其结构设计、材质、加工精度、安装和调节精度决定了其维修保养要求和使用寿命。电动伸缩门电气组件的寿命主要与不当使用和偶然事故有关。
The basic components of the electric expansion door are guide rail, pulley and drive belt. Because these three parts are directly related to the operation of the electric expansion door and are vulnerable parts under the normal use conditions of the electric expansion door, its structural design, material, processing accuracy, installation and adjustment accuracy determine its maintenance requirements and service life. The service life of the electric components of the electric expansion door is mainly related to improper use and accidental accidents.
长期以来，电动伸缩门滑轨的设计完全不同于非电动伸缩门滑轨的设计。后者通常有两道水平方向的平行滑轨，两个(或四个)滑轮通过中间的连接件与悬挂的移动门体相连，移动门体的重心恰好在两道滑轨的支撑力之间，形成稳定的"正悬挂"，这种稳定的结构可以达到很好的稳定性和静音效果。但是，电动伸缩门的滑轨由于要兼顾与门框的固定、门体吊挂及调节、电气组件的安装和外饰盖板的安装等功能，所以最简单的办法就是将滑轨设计成单侧滑道，门体在一侧通过滑轮侧向吊挂在滑轨上，形成侧悬挂。这种设计的优点是安装和调节门体方便、维修也容易。但是，这种设计有许多致命的弱点。
For a long time, the design of slide rail of electric expansion door is totally different from that of non electric expansion door. The latter usually has two parallel slideways in horizontal direction. Two (or four) pulleys are connected with the suspended moving door body through the middle connecting piece. The center of gravity of the moving door body is just between the supporting forces of the two slideways, forming a stable "positive suspension". This stable structure can achieve good stability and quiet effect. However, the slide rail of the electric expansion door should take into account the functions of fixing the door frame, hanging and adjusting the door body, installing the electrical components and installing the exterior decoration cover plate, so the simplest way is to design the slide rail as a one-sided slide, and the door body is hung on the slide rail laterally through the pulley at one side to form a side suspension. The advantage of this design is that it is convenient to install and adjust the door body and easy to maintain. However, this design has many fatal weaknesses.
所以使用这种电动伸缩门必须注意保养和维护滑轮与导轨上部间隙容易使门体滑落，使用的安全性得不到保证。所以选择这种电动伸缩门必须注意电动伸缩门的抗风压强度。这种不稳定的运行使驱动器负载不断变化，对电气组件的使用寿命影响极大。侧悬挂结构，对门体向上的支撑力都在一条线上，门体重心由于安装精度的误差和风力的影响.使门体不仅形成静态侧摆也产生动态侧摆。为此.这种电动伸缩门门体下部的导向块，通常称为"止摆块"，就使用一种轴承，轴承直径小于门体下部导槽，使门体在两方向摆动的条件下依然可以运行。这种侧摆产生的震动在使用效果上表现为噪音，其后果必然导致滑轮和导轨的磨损。
Therefore, when using this kind of electric expansion door, it is necessary to pay attention to the maintenance and repair of the upper clearance between the pulley and the guide rail, so that the door body may slide down easily, and the safety of use cannot be guaranteed. Therefore, it is necessary to pay attention to the anti wind pressure strength of the electric expansion door when selecting this kind of electric expansion door. This kind of unstable operation makes the load of the driver constantly changing, which has a great impact on the service life of the electrical components. The side suspension structure has a line of upward supporting force on the door body. The center of gravity of the door body not only forms static side sway but also dynamic side sway due to the error of installation accuracy and the influence of wind force. For this reason, the guide block at the lower part of the electric expansion door body, commonly known as the "stop block", uses a bearing whose diameter is smaller than the guide slot at the lower part of the door body, so that the door body can still operate under the condition of two-way swing. The vibration produced by the side sway is noise in the use effect, which will inevitably lead to the wear of pulley and guide rail.