本帖最后由 chase_1987 于 2013-3-18 22:27 编辑 + k2 g# |: B, q; h7 F
0 K# h% q! ~8 iI have read something about belt drive these two days. I have reviewed belt drive in my college textbook named 《Mechanical Design》. For the sake of learning Mechanical English, I also read belt drive in an English book named 《Machine elements in Mechanical Design》. I think may be a good way to learn Mechanical English. Since you have read the Chinese version prior to the English version, you will not find it difficult to understand the mechanical phrases in the English book. Summary is very important when you have just learned something. And making summaries is a very important step to help you remember what you have learned firmly. I will make this a habit in the following days. Belt drive: 1. Many types of belts are available: flat belts; grooved or cogged belts; standard V-belts; narrow V-belts; double angle V-belts; and others. 2. Advantages of belt drive: a. Ease the impact load b. Operate smoothly with low noise c. Low manufacture and assembly precision d. Overload protection e. Large center distance can be reached 3. Disadvantages of belt drive: a. Low transmission efficiency b. Short belt life c. Speed ratio is not accurate because of elastic slip 4. Flat belt can be in any length. We can cut it as we need. Then we connect it and the connectors may make the operation not smooth. 5. V-belt has no connectors. So we have to choose a standard length for a V-belt. 6. Cog V-belts which are applied to standard V-grooved sheaves have a longer life. The cogs give the belt greater flexibility and higher efficiency compared with standard belts. They can operate on smaller sheaves. 7. The value of the initial tension force and the angle of wrap cannot be too low. 8. Because of elastic slip, the output sheave has a lower speed than the input sheave. 9. Elastic slip which cannot be eliminated will cause the rise of temperature. 10. V-belt is the most widely used type of all the belts. 11. Narrow V-belt is better than standard V-belt and it can totally replace standard V-belt. | 
发表于 2013-3-18 22:20:33
