希望你采纳最佳答案,我花了三天三夜翻译的3.1 : abnormal verification3.1.1 this Division I received customer returned defective 3PCS, D / C were 0272 / 0166 / 9436, which were numbered 01 # 02 # 03 #, test its appearance has locking traces of products fan and its frame has a relatively thick dust, lead terminal are connected with the Department of electronic components, in addition 01 # products fan blade fracture 1PCS, 02 # products fan blade fracture 4PCS, 03 # products fan blade fracture 6PCS ( this type fan blade, a total of 7PCS). As shown below :3.2.1 respectively in 01 # 02 # 03 # further analysis, found the broken blade blade edge has the varying degree damage sag deformation, ( as shown below ), which is inferred for the fan in the high-speed operation when the upper edge of the blade and the other object body contact, leading to edge damage.3.2.2 further observations on its blade fracture, fracture analysis of traces left by the blade cracks highlight, fracture edges left deep right shallower, we conclude that for the left to right after the first force ; the other consists of fracture can be found on the edge of the lower edge is higher, therefore we can conclude that the upper edge for the first stress surface, after Wei downward edge, have further proved the upper edge and other objects have contact. In conclusion can be deduced : fan leaf is from left to right to fracture, namely to the running direction of the reverse side of the fracture, ( fan for counterclockwise movement). As shown below :Analysis of abnormal test : 3.33.3.1 from the above analysis can be inferred : fan blade fracture may be due to the fan at high speed operation ( this machine is a high speed rotating type, high), the fan blades and the other object collision contact, causing the fan blade by the reverse force and fracture.4.1.1 consists of blade fracture traces can be launched: fan at high speed operation with other objects in contact mechanics principle. According to the object in high speed operation, due to the relatively high speed, constant quality, speed of the kinetic energy is big, and other objects colliding will produce tremendous counterforce which leads to fracture.6.1.1 recommends that customers in the use of the fan when the fan blades and other objects to avoid contact and interference, which led to the blade damage.