An automatic transmission is a device that is connected to the back of an engine and sends the power from the engine to the drive wheels. Its job is to keep the engine within a certain angular velocity. Although there are many epicyclic-type automatic transmissions in production, the related configuration design methods are still tedious and prone to human error. A simple and analytic methodology needs to be developed. Therefore, the purpose of this research is to present an efficient methodology for the systematic design of the epicyclic gear transmissions for automobiles. First, fundamentals and gear-shifting operations of the four-speed, five-speed and six-speed epicyclic-type automatic transmissions are illustrated to establish the design requirements. Second, based on the kinematic equations of the fundamental geared entities and the corresponding basic gear ratios, a procedure is applied to execute the kinematic and mechanical-efficiency analyses for the automatic transmissions. Third, two simple clutching-sequence synthesis methods are proposed and illustrated. One is based on the speed ratio equations, and another is based on the lever diagram. Next, a planar-graph representation is presented to arrange the desired clutches for each possible clutching sequence into the epicyclic gear mechanism. Then, the number of teeth of each gear is synthesized from assigning two or three desired speed ratios by the analytic method. Finally, a computer-aided design program for the clutching-sequence synthesis is developed with the considerations of the design requirements. With the above methods, the systematic designs of the 204 epicylic gear mechanisms are given for demonstrating the feasibility of the proposed methodology. The result of this work shows that the seven-link two-DOF epicylic gear mechanisms, the eight-link two-DOF Ravigneaux gear mechanism, and the nine-link two-DOF parallel-connected epicylic gear mechanisms could reach four-, six-, and six-forward speeds at most, respectively.
| Identifer | oai:union.ndltd.org:NSYSU/oai:NSYSU:etd-0209109-121326 |
| Date | 09 February 2009 |
| Creators | Huang, Ruei-Hong |
| Contributors | Deng-Maw Lu, Inn-Chyn Her, Chi-Feng Chang, Tyng Liu, Chiu-Feng Lin, Chung-Ching Lee, Cheng-Ho Hsu, Li-Chun Wang ยก@ |
| Publisher | NSYSU |
| Source Sets | NSYSU Electronic Thesis and Dissertation Archive |
| Language | Cholon |
| Detected Language | English |
| Type | text |
| Format | application/pdf |
| Source | http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0209109-121326 |
| Rights | not_available, Copyright information available at source archive |
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