Experimental and numerical analyses for the effect of the thickness of gap generator blank（GGB） on the formability of the outer blanks were investigated. The thickness of the GGB has the greatest impact on the thinn...Experimental and numerical analyses for the effect of the thickness of gap generator blank（GGB） on the formability of the outer blanks were investigated. The thickness of the GGB has the greatest impact on the thinning of the lowest blank. In addition, the friction at different regions and the additional interlayer contacts can also affect the thinning of different regions as well as increase the punch force. This work will enhance the understanding of simultaneous multi-layered blanks forming and will help the composite design engineers to tailor requirement-specific hybrid parts such as fiber metal laminates（FMLs） and functionally graded structures（FGSs） for hi-tech applications.展开更多
Cam profiles play an important part in the performance of cam mechanisms. Syntheses of cam profile designs and dynamics of cam designs are studied at first. Then, a cam profile design optimization model based on the s...Cam profiles play an important part in the performance of cam mechanisms. Syntheses of cam profile designs and dynamics of cam designs are studied at first. Then, a cam profile design optimization model based on the six order classical spline and single DOF(degree of freedom) dynamic model of single-dwell cam mechanisms is developed. And dynamic constraints such as jumps and vibrations of followers are considered. This optimization model, with many advantages such as universalities of applications, conveniences to operations and good performances in improving kinematic and dynamic properties of cam mechanisms, is good except for the discontinuity of jerks at the end knots of cam profiles which will cause vibrations of cam systems. However, the optimization is improved by combining the six order classical spline with general polynomial spline which is the so-called "trade-offs". Finally, improved optimization is proven to have a better performance in designing cam profiles.展开更多
基金Project(2010DFA52030)supported by the International Scientific Cooperation,ChinaProject(51175024)supported by the National Natural Science Foundation of China
文摘Experimental and numerical analyses for the effect of the thickness of gap generator blank（GGB） on the formability of the outer blanks were investigated. The thickness of the GGB has the greatest impact on the thinning of the lowest blank. In addition, the friction at different regions and the additional interlayer contacts can also affect the thinning of different regions as well as increase the punch force. This work will enhance the understanding of simultaneous multi-layered blanks forming and will help the composite design engineers to tailor requirement-specific hybrid parts such as fiber metal laminates（FMLs） and functionally graded structures（FGSs） for hi-tech applications.
文摘Cam profiles play an important part in the performance of cam mechanisms. Syntheses of cam profile designs and dynamics of cam designs are studied at first. Then, a cam profile design optimization model based on the six order classical spline and single DOF(degree of freedom) dynamic model of single-dwell cam mechanisms is developed. And dynamic constraints such as jumps and vibrations of followers are considered. This optimization model, with many advantages such as universalities of applications, conveniences to operations and good performances in improving kinematic and dynamic properties of cam mechanisms, is good except for the discontinuity of jerks at the end knots of cam profiles which will cause vibrations of cam systems. However, the optimization is improved by combining the six order classical spline with general polynomial spline which is the so-called "trade-offs". Finally, improved optimization is proven to have a better performance in designing cam profiles.
