Linkage or cam follower types of mechanisms are designed to create dwell motion when the interest of point on the mechanism is expected to stay at rest while the input is constantly supplied to the driven link. Generally, six bar linkages consisting of a four bar crank rocker mechanism actuating a slider crank are considered for linkage type mechanisms. A novel compliant translational double exact dwell mechanism incorporating the buckling motion of an initially straight flexible member as its members is introduced in this paper. Buckling members are designed to create dwell motion as a compliant mechanism that is easy to manufacture and require minimum number of components and assembly.

This partially compliant five bar mechanism consists of two rigid links as the crank and the slider, and two flexible links as the coupler and the last link. Kinematic analysis of the mechanism is broken into two parts. The first one is a flexible pinned-pinned beam attached to a slider and the second one is the pinned-pinned flexible beam which is attached to a rotating crank. Large deflection analysis of pinned-pinned buckling beam is obtained by solving first and second kind of elliptic integrals in Matlab. Load required to displace the slider and the maximum bending moment restored on the pinned-pinned beam are analyzed by changing the normalized offset from 0 to 1.

A mechanism is said to be linear if the slope of the load-deflection curve remains positive during deformation. Slope of the normalized load deflection curves at various offsets are explored and design limitations providing a stable buckling behavior is discussed. Pinned-pinned buckling beams are represented by springs possessing the same load-deflection characteristics as the compliant beams where the nonlinear spring function is described by a 4th order polynomials fitted to the load-deflection curves both for the beam attached to the slider and the beam attached to the driven crank. The emphasis is placed on the dynamic response of the double exact dwell motion profile. Simulation results are studied using Solidworks model, and Matlab. Slider stays at rest until the maximum bending moment of the coupler flexible link is achieved creating the dwell, snaps to its maximum position and on the return creates a momentary dwell since the flexible follower behaves like a rigid link. Desired dwell motion can be accomplished by changing the flexible beam parameters such as its length, thickness and offset ratio.

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