标题: 以弹性皮带达成自动变速的新式理论之验证
Verification of a Principle for Automatic Transmission Utilizing an Elastic Belt
作者: 萧士芸
洪锡源
机械工程学系
关键字: 自动变速;无段变速;变速;皮带;Automatic Transmission;continuously variable transmission;CVT;transmission;belt
公开日期: 2006
摘要: 无段变速技术(CVT)自1877年诞生以来,开始在变速器市场上展露头角,预计将成为未来变速器的主流。但纵观目前所有型式的变速器,改变速比皆牵涉力的传递时作用在输入轴与输出轴上的有效半径比。本研究的目的为分析并以实验验证一种全自动无段变速的新式理论。
此新式变速理论使用一条可以弹性变形的皮带联结固定尺寸的驱动轮与被动轮,速比的改变并非改变皮带于皮带轮上之有效半径,而是利用皮带本身在负载增加时被拉长而使速比下降。此种新式理论可以简化变速器设计并提升其效率。将来此种变速器不需人为操作,是完全自我侦测、自我调整的全自动无段变速器。
本论文首先提出本新式理论的中心概念与假设,再以皮带传动的力学讨论对此新式理论加以分析,并依此新式变速方式的需求设计变速器及其传动皮带,最后以实验的方式验证此新式变速理论。
实验结果成功地在小负载与低转速的情况下实现此种新式变速理论。以皮带受不同张力所产生不同的弹性变形来改变速比及扭力比在本研究中被验证为可行的,并且针对实验过程中所发现的现象提出供以后研究方向与设计改良的建议,已为此种新式变速理论奠定基础并提供参考。
From 1877, the continuously variable transmission (CVT) showed up and became popular in the transmission market, and it is expected to be the main stream of transmission in the future. This research attempts to verify a new principle for automatic continuously variable transmission which is achieved by elastic deformation of an elastic belt.
Unlike traditional transmission, this new approach does not rely on the gear ratio or the radius of the driving and driven wheel to change the speed ratio. The speed change in this new approach is achieved by an elastic belt on two fixed-diameter pulleys. The belt elongates in proportion to the load applied, and the driving pulley has to rotate more to accommodate the increased length of the belt due to the load increase. This means the speed of driven pulley will automatically reduce when the load increase. This new CVT is self-sensing, self-adjusting, and fully automatic.
This thesis introduces the main concept and assumption of the new principle, conducts mechanic analysis, designs and builds the transmission model and an elastic belt, and experimentally verifies the new principle.
The result of experiment shows that the new transmission succeeds when the load is small and the speed is low. It proves the feasibility of using the deformation of the elastic belt to change speed ratio and torque ratio. Based on this result, a whole new transmission may be designed, manufactured, improved, and used in the future.
URI: http://140.113.39.130/cdrfb3/record/nctu/#GT009414539
http://hdl.handle.net/11536/80939
显示于类别:Thesis