181 x 176 (millimeters, width x depth) 239 x 245 x 257 (millimeters, width x depth x height)
Description:
This model contains several variations of the so-called 'lazy tongs' mechanism. The principal constraint consists of crossed links with a center pin and slider pins in slots in two parallel links. Closing the angle between the crossed links moves the two parallel links apart while maintaining the vertical orientation of these two links. An extension of this mechanism is the connection of two or more pairs of crossed links with center pins that will amplify the relative motion of the two parallel links for a given change in angle of the crossed links. This constitutes an exact parallel mechanism in contrast to the approximate parallel mechanism of Models T3-T10. Variations of the lazy tongs mechanism have appeared in the history of machines including the manuscripts of Leonardo da Vinci (c.1500), and the machine books of Jacque Besson (C. 1570), and Ramelli (c. 1580). A similar mechanism has been used in electric trains in the power pickup mechanism sometimes called a pantograph. It has also been used in hydraulic lift devices from automobile jacks to mobile worker lift platforms. [Francis Moon, 2003-07-01] The 220 models in Cornell University’s Reuleaux Collection were built in the late 19th century to demonstrate the elements of machine motion, as theorized by the German engineer Franz Reuleaux. The University acquired the models in 1882 for use in teaching and research. The Reuleaux models are classified according to the alphanumeric schema employed in the catalog of the manufacturer, Gustav Voigt. The letter in a model's ID (e.g., B14 or S35) refers to a class of mechanism; the number is a specific instance of the class. This classification scheme is a simplified version of the taxonomy of machine elements elaborated in Reuleaux's work.
Photography credit: Jon Reis (www.jonreis.com). Jon Reis Photography grants Cornell University Libraries and the Cornell College of Engineering the rights to display copyrighted images of the Reuleux collection of kinetic machines on the Cornell University and National Science Digital Library web sites and for unlimited use in Cornell University Library publications for education purposes only. Rights for all other uses, including but not limited to, editorial, commercial, advertising, web use and display by third parties not affiliated with Cornell University are reserved by the photographer. The written permission of any copyright and other rights holders is required for distribution, reproduction, or other use that extends beyond what is authorized by fair use and other statutory exemptions. Responsibility for making an independent legal assessment of an item and securing any necessary permissions ultimately rests with persons desiring to use the item. For questions about this item or other items please contact the Physical Sciences Librarians at pslref@cornell.edu.
