On the Dynamic Balance of a Planar Four-Bar Mechanism with a Flexible Coupler

Abstract

The dynamic balance of planar mechanisms with flexible links is considered. A balancing principle for a single prismatic beam with a number of support points is developed, which is based on modal balancing. The cases with two and four support points are applied to a planar four-bar mechanism with a flexible coupler and the results are compared with the case in which the coupler is hinged at its ends and the case in which it is supported at reciprocal points. It is shown in an example that the shaking forces can be reduced by a factor of up to 200, but that it is more difficult also to balance the shaking moment.