Rotational joints are widely used in broad range of applications as they are able to bear angular irregularities of input and output shafts. Rotational joint failure can be caused by wear, error during manufacturing, error during assembly or incorrect usage. For the purpose of this thesis we focused on failures caused by fatigue. This thesis contains analysis of 6 different rotational joints that have fundamental functionality in common. At first we specified conditions of operation, and looked for construction solutions of each individual joint, based on sketches and descriptions. Based on 3D models, we carried out kinematic and structural analysis. The result of tension states of structural analysis was used for numerical calculation of stress cycles until each type of joint failed. We discovered that universal joint is the most resistant to fatigue and as such, most commonly used in practice, although other types of rotational joints do have an advantage over it in a better angular velocity profile on the output, which makes an impact on all elements of the drivetrain behind the joint.
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