Development of low strain clamping device for compliant parts apply-ing characteristics of Electro-Rheological Fluid

由于夹紧力引起的零件变形是制造或测量过程中需要解决的问题之一，这些过程需要极高的精度。特别是，由于夹紧力小，容易变形，因此很难夹紧薄而柔顺的零件而不发生弹性变形。本文研制了一种新型的机械三点支撑夹紧装置。将电流变液（ERF）的特性应用到夹紧驱动器中。ERF是一种胶体悬浮液，其表观粘度随外加电场强度的变化而变化，并提供屈服应力。开发了ERF离合器元件并安装在夹紧装置上。夹紧力是通过控制外加电场强度的ERF夹紧执行器来控制的。从夹紧力容量、被夹件残余应变和装置搬运过程中零件持稳性三个方面对所研制的ERF装置进行了性能评价。结果总结如下：(1)当对浮式减振器施加较小的外力（最大2.45 N）时，浮式减振器通过ERF膜离合器夹紧在静止减振器上，浮式减振器与静止减振器之间的相对位移被ERE效应成功地抑制。(2)通过控制施加在ERF离合器上的电场强度，使夹紧装置上的薄型柔顺零件的弹性变形降到极低的水平。

The deformation of the parts due to the clamping force is one of the issues to be solved in manufacturing or measuring process where extremely high accuracy is required. Especially, it is difficult to clamp the thin andd compliant parts without the elastic deformation, because they are easily deformed by the small clamping force.In this research, a new mechanical three-point-support clamping device is developed. The characteristics of electrorheological fluid (ERF) is applied to the clamping actuator. The ERF is a kind of colloidal suspension, whose apparent viscosity is variable depending on the applied electric field intensity and it provides the yield stress. The ERF clutch element is developed and installed to the clamping device. The clamping force is simply controlled by controlling the applied electric field intensity to the ERF clamping actuators. The performance of the developed ERF device was evaluated from the viewpoint of capacity of clamping force, residual strain on the clamped parts and parts holding stability during carry of devices. The results are summarized as follows ;(1) When the small external force (Max. 2.45 N) is applied to the floating damper which is clamped to the stationary damper by the ERF film clutch, the relative displacement between the floating damper and stationary damper is successfully suppressed to him by the ERE effect.(2) The elastic deformation of the thin and compliant parts on the clamping devise is reduced to the extremely low level by controlling the applied electric field intensity to the ERF clutch.